text: /*!
   *  howler.js v2.0.2
   *  howlerjs.com
   *
   *  (c) 2013-2016, James Simpson of GoldFire Studios
   *  goldfirestudios.com
   *
   *  MIT License
   */
  
  (function() {
  
    'use strict';
  
    /** Global Methods **/
    /***************************************************************************/
  
    /**
     * Create the global controller. All contained methods and properties apply
     * to all sounds that are currently playing or will be in the future.
     */
    var HowlerGlobal = function() {
      this.init();
    };
    HowlerGlobal.prototype = {
      /**
       * Initialize the global Howler object.
       * @return {Howler}
       */
      init: function() {
        var self = this || Howler;
  
        // Internal properties.
        self._codecs = {};
        self._howls = [];
        self._volume = 1;
        self._canPlayEvent = 'canplaythrough';
        self._navigator = (typeof window !== 'undefined' && window.navigator) ? window.navigator : null;
  
        // Public properties.
        self.masterGain = null;
        self.noAudio = false;
        self.usingWebAudio = true;
        self.autoSuspend = true;
        self.ctx = null;
  
        // Set to false to disable the auto iOS enabler.
        self.mobileAutoEnable = true;
  
        // Setup the various state values for global tracking.
        self._setup();
  
        return self;
      },
  
      /**
       * Get/set the global volume for all sounds.
       * @param  {Float} vol Volume from 0.0 to 1.0.
       * @return {Howler/Float}     Returns self or current volume.
       */
      volume: function(vol) {
        var self = this || Howler;
        vol = parseFloat(vol);
  
        // If we don't have an AudioContext created yet, run the setup.
        if (!self.ctx) {
          setupAudioContext();
        }
  
        if (typeof vol !== 'undefined' && vol >= 0 && vol <= 1) {
          self._volume = vol;
  
          // When using Web Audio, we just need to adjust the master gain.
          if (self.usingWebAudio) {
            self.masterGain.gain.value = vol;
          }
  
          // Loop through and change volume for all HTML5 audio nodes.
          for (var i=0; i<self._howls.length; i++) {
            if (!self._howls[i]._webAudio) {
              // Get all of the sounds in this Howl group.
              var ids = self._howls[i]._getSoundIds();
  
              // Loop through all sounds and change the volumes.
              for (var j=0; j<ids.length; j++) {
                var sound = self._howls[i]._soundById(ids[j]);
  
                if (sound && sound._node) {
                  sound._node.volume = sound._volume * vol;
                }
              }
            }
          }
  
          return self;
        }
  
        return self._volume;
      },
  
      /**
       * Unload and destroy all currently loaded Howl objects.
       * @return {Howler}
       */
      unload: function() {
        var self = this || Howler;
  
        for (var i=self._howls.length-1; i>=0; i--) {
          self._howls[i].unload();
        }
  
        // Create a new AudioContext to make sure it is fully reset.
        if (self.usingWebAudio && self.ctx && typeof self.ctx.close !== 'undefined') {
          self.ctx.close();
          self.ctx = null;
          setupAudioContext();
        }
  
        return self;
      },
  
      /**
       * Check for codec support of specific extension.
       * @param  {String} ext Audio file extention.
       * @return {Boolean}
       */
      codecs: function(ext) {
        return (this || Howler)._codecs[ext.replace(/^x-/, '')];
      },
  
      /**
       * Setup various state values for global tracking.
       * @return {Howler}
       */
      _setup: function() {
        var self = this || Howler;
  
        // Keeps track of the suspend/resume state of the AudioContext.
        self.state = self.ctx ? self.ctx.state || 'running' : 'running';
  
        // Automatically begin the 30-second suspend process
        self._autoSuspend();
  
        // Check if audio is available.
        if (!self.usingWebAudio) {
          // No audio is available on this system if noAudio is set to true.
          if (typeof Audio !== 'undefined') {
            try {
              var test = new Audio();
  
              // Check if the canplaythrough event is available.
              if (typeof test.oncanplaythrough === 'undefined') {
                self._canPlayEvent = 'canplay';
              }
            } catch(e) {
              self.noAudio = true;
            }
          } else {
            self.noAudio = true;
          }
        }
  
        // Test to make sure audio isn't disabled in Internet Explorer.
        try {
          var test = new Audio();
          if (test.muted) {
            self.noAudio = true;
          }
        } catch (e) {}
  
        // Check for supported codecs.
        if (!self.noAudio) {
          self._setupCodecs();
        }
  
        return self;
      },
  
      /**
       * Check for browser support for various codecs and cache the results.
       * @return {Howler}
       */
      _setupCodecs: function() {
        var self = this || Howler;
        var audioTest = null;
  
        // Must wrap in a try/catch because IE11 in server mode throws an error.
        try {
          audioTest = (typeof Audio !== 'undefined') ? new Audio() : null;
        } catch (err) {
          return self;
        }
  
        if (!audioTest || typeof audioTest.canPlayType !== 'function') {
          return self;
        }
  
        var mpegTest = audioTest.canPlayType('audio/mpeg;').replace(/^no$/, '');
  
        // Opera version <33 has mixed MP3 support, so we need to check for and block it.
        var checkOpera = self._navigator && self._navigator.userAgent.match(/OPR\/([0-6].)/g);
        var isOldOpera = (checkOpera && parseInt(checkOpera[0].split('/')[1], 10) < 33);
  
        self._codecs = {
          mp3: !!(!isOldOpera && (mpegTest || audioTest.canPlayType('audio/mp3;').replace(/^no$/, ''))),
          ogg: !!audioTest.canPlayType('audio/ogg; codecs="vorbis"').replace(/^no$/, '')
        };
  
        return self;
      },
  
      /**
       * Mobile browsers will only allow audio to be played after a user interaction.
       * Attempt to automatically unlock audio on the first user interaction.
       * Concept from: http://paulbakaus.com/tutorials/html5/web-audio-on-ios/
       * @return {Howler}
       */
      _enableMobileAudio: function() {
        var self = this || Howler;
  
        // Only run this on mobile devices if audio isn't already eanbled.
        var isMobile = /iPhone|iPad|iPod|Android|BlackBerry|BB10|Silk|Mobi/i.test(self._navigator && self._navigator.userAgent);
        var isTouch = !!(('ontouchend' in window) || (self._navigator && self._navigator.maxTouchPoints > 0) || (self._navigator && self._navigator.msMaxTouchPoints > 0));
        if (self._mobileEnabled || !self.ctx || (!isMobile && !isTouch)) {
          return;
        }
  
        self._mobileEnabled = false;
  
        // Some mobile devices/platforms have distortion issues when opening/closing tabs and/or web views.
        // Bugs in the browser (especially Mobile Safari) can cause the sampleRate to change from 44100 to 48000.
        // By calling Howler.unload(), we create a new AudioContext with the correct sampleRate.
        if (!self._mobileUnloaded && self.ctx.sampleRate !== 44100) {
          self._mobileUnloaded = true;
          self.unload();
        }
  
        // Scratch buffer for enabling iOS to dispose of web audio buffers correctly, as per:
        // http://stackoverflow.com/questions/24119684
        self._scratchBuffer = self.ctx.createBuffer(1, 1, 22050);
  
        // Call this method on touch start to create and play a buffer,
        // then check if the audio actually played to determine if
        // audio has now been unlocked on iOS, Android, etc.
        var unlock = function() {
          // Create an empty buffer.
          var source = self.ctx.createBufferSource();
          source.buffer = self._scratchBuffer;
          source.connect(self.ctx.destination);
  
          // Play the empty buffer.
          if (typeof source.start === 'undefined') {
            source.noteOn(0);
          } else {
            source.start(0);
          }
  
          // Setup a timeout to check that we are unlocked on the next event loop.
          source.onended = function() {
            source.disconnect(0);
  
            // Update the unlocked state and prevent this check from happening again.
            self._mobileEnabled = true;
            self.mobileAutoEnable = false;
  
            // Remove the touch listener.
            document.removeEventListener('touchstart', unlock, true);
            document.removeEventListener('touchend', unlock, true);
            document.removeEventListener('click', unlock, true);
          };
        };
  
        // Setup a touch listener to attempt an unlock in.
        document.addEventListener('touchstart', unlock, true);
        document.addEventListener('touchend', unlock, true);
        document.addEventListener('click', unlock, true);
  
        return self;
      },
  
      /**
       * Automatically suspend the Web Audio AudioContext after no sound has played for 90 seconds.
       * This saves processing/energy and fixes various browser-specific bugs with audio getting stuck.
       * @return {Howler}
       */
      _autoSuspend: function() {
        var self = this;
  
        if (!self.autoSuspend || !self.ctx || typeof self.ctx.suspend === 'undefined' || !Howler.usingWebAudio) {
          return;
        }
  
        // Check if any sounds are playing.
        for (var i=0; i<self._howls.length; i++) {
          if (self._howls[i]._webAudio) {
            return self._howls[i]._sounds.length > 0;
          }
        }
  
        if (self._suspendTimer) {
          clearTimeout(self._suspendTimer);
        }
  
        // If no sound has played after 90 seconds, suspend the context.
        self._suspendTimer = setTimeout(function() {
          if (!self.autoSuspend) {
            return;
          }
  
          self._suspendTimer = null;
          self.state = 'suspending';
          self.ctx.suspend().then(function() {
            self.state = 'suspended';
  
            if (self._resumeAfterSuspend) {
              delete self._resumeAfterSuspend;
              self._autoResume();
            }
          });
        }, 90000);
  
        return self;
      },
  
      /**
       * Automatically resume the Web Audio AudioContext when a new sound is played.
       * @return {Howler}
       */
      _autoResume: function() {
        var self = this;
  
        if (!self.ctx || typeof self.ctx.resume === 'undefined' || !Howler.usingWebAudio) {
          return;
        }
  
        if (self.state === 'running' && self._suspendTimer) {
          clearTimeout(self._suspendTimer);
          self._suspendTimer = null;
        } else if (self.state === 'suspended') {
          self.state = 'resuming';
          self.ctx.resume().then(function() {
            self.state = 'running';
  
            // Emit to all Howls that the audio has resumed.
            for (var i=0; i<self._howls.length; i++) {
              self._howls[i]._emit('resume');
            }
          });
  
          if (self._suspendTimer) {
            clearTimeout(self._suspendTimer);
            self._suspendTimer = null;
          }
        } else if (self.state === 'suspending') {
          self._resumeAfterSuspend = true;
        }
  
        return self;
      }
    };
  
    // Setup the global audio controller.
    var Howler = new HowlerGlobal();
  
    /** Group Methods **/
    /***************************************************************************/
  
    /**
     * Create an audio group controller.
     * @param {Object} o Passed in properties for this group.
     */
    var Howl = function(o) {
      var self = this;
  
      // Throw an error if no source is provided.
      if (!o.src || o.src.length === 0) {
        console.error('An array of source files must be passed with any new Howl.');
        return;
      }
  
      self.init(o);
    };
    Howl.prototype = {
      /**
       * Initialize a new Howl group object.
       * @param  {Object} o Passed in properties for this group.
       * @return {Howl}
       */
      init: function(o) {
        var self = this;
  
        // If we don't have an AudioContext created yet, run the setup.
        if (!Howler.ctx) {
          setupAudioContext();
        }
  
        // Setup user-defined default properties.
        self._format = (typeof o.format !== 'string') ? o.format : [o.format];
        self._html5 = o.html5 || false;
        self._pool = o.pool || 5;
        self._preload = (typeof o.preload === 'boolean') ? o.preload : true;
        self._src = (typeof o.src !== 'string') ? o.src : [o.src];
        self._volume = o.volume !== undefined ? o.volume : 1;
  
        // Setup all other default properties.
        self._duration = 0;
        self._state = 'unloaded';
        self._sounds = [];
        self._endTimers = {};
        self._queue = [];
  
        // Setup event listeners.
        self._onload = self._onloaderror = self._onpause = self._onplay = self._onstop = self._onvolume = self._onresume = [];
        self._onend = o.onend ? [{fn: o.onend}] : [];
  
        // Web Audio or HTML5 Audio?
        self._webAudio = Howler.usingWebAudio && !self._html5;
  
        // Automatically try to enable audio on iOS.
        if (typeof Howler.ctx !== 'undefined' && Howler.ctx && Howler.mobileAutoEnable) {
          Howler._enableMobileAudio();
        }
  
        // Keep track of this Howl group in the global controller.
        Howler._howls.push(self);
  
        // Load the source file unless otherwise specified.
        if (self._preload) {
          self.load();
        }
  
        return self;
      },
  
      /**
       * Load the audio file.
       * @return {Howler}
       */
      load: function() {
        var self = this;
        var url = null;
  
        // If no audio is available, quit immediately.
        if (Howler.noAudio) {
          self._emit('loaderror', null, 'No audio support.');
          return;
        }
  
        // Make sure our source is in an array.
        if (typeof self._src === 'string') {
          self._src = [self._src];
        }
  
        // Loop through the sources and pick the first one that is compatible.
        for (var i=0; i<self._src.length; i++) {
          var ext, str;
  
          if (self._format && self._format[i]) {
            // If an extension was specified, use that instead.
            ext = self._format[i];
          } else {
            // Make sure the source is a string.
            str = self._src[i];
            if (typeof str !== 'string') {
              self._emit('loaderror', null, 'Non-string found in selected audio sources - ignoring.');
              continue;
            }
  
            // Extract the file extension from the URL or base64 data URI.
            ext = /^data:audio\/([^;,]+);/i.exec(str);
            if (!ext) {
              ext = /\.([^.]+)$/.exec(str.split('?', 1)[0]);
            }
  
            if (ext) {
              ext = ext[1].toLowerCase();
            }
          }
  
          // Check if this extension is available.
          if (Howler.codecs(ext)) {
            url = self._src[i];
            break;
          }
        }
  
        if (!url) {
          self._emit('loaderror', null, 'No codec support for selected audio sources.');
          return;
        }
  
        self._src = url;
        self._state = 'loading';
  
        // If the hosting page is HTTPS and the source isn't,
        // drop down to HTML5 Audio to avoid Mixed Content errors.
        if (window.location.protocol === 'https:' && url.slice(0, 5) === 'http:') {
          self._html5 = true;
          self._webAudio = false;
        }
  
        // Create a new sound object and add it to the pool.
        new Sound(self);
  
        // Load and decode the audio data for playback.
        if (self._webAudio) {
          loadBuffer(self);
        }
  
        return self;
      },
  
      /**
       * Play a sound or resume previous playback.
       * @param  {String/Number} sprite   **REMOVED** Sprite name for sprite playback or sound id to continue previous.
       * @param  {Boolean} internal Internal Use: true prevents event firing.
       * @return {Number}          Sound ID.
       */
      play: function(_, internal) {
        var self = this;
  
        // Get the selected node, or get one from the pool.
        var sound = self._inactiveSound();
  
        // If we have no sprite and the sound hasn't loaded, we must wait
        // for the sound to load to get our audio's duration.
        if (self._state !== 'loaded' && !self._sprite) {
          self._queue.push({
            event: 'play',
            action: function() {
              self.play(self._soundById(sound._id) ? sound._id : undefined);
            }
          });
  
          return sound._id;
        }
  
        // Make sure the AudioContext isn't suspended, and resume it if it is.
        if (self._webAudio) {
          Howler._autoResume();
        }
  
        // Determine how long to play for and where to start playing.
        var seek = Math.max(0, self._sprite[0] / 1000);
        var duration = Math.max(0, ((self._sprite[0] + self._sprite[1]) / 1000) - seek);
        var timeout = duration * 1000;
  
        // Update the parameters of the sound
        sound._ended = false;
        sound._start = self._sprite[0] / 1000;
        sound._stop = (self._sprite[0] + self._sprite[1]) / 1000;
  
        // Begin the actual playback.
        var node = sound._node;
        if (self._webAudio) {
          // Fire this when the sound is ready to play to begin Web Audio playback.
          var playWebAudio = function() {
            self._refreshBuffer(sound);
  
            // Setup the playback params.
            var vol = sound._volume;
            node.gain.setValueAtTime(vol, Howler.ctx.currentTime);
            sound._playStart = Howler.ctx.currentTime;
  
            // Play the sound using the supported method.
            if (typeof node.bufferSource.start === 'undefined') {
              node.bufferSource.noteGrainOn(0, seek, duration);
            } else {
              node.bufferSource.start(0, seek, duration);
            }
  
            // Start a new timer if none is present.
            if (timeout !== Infinity) {
              self._endTimers[sound._id] = setTimeout(self._ended.bind(self, sound), timeout);
            }
  
            if (!internal) {
              setTimeout(function() {
                self._emit('play', sound._id);
              }, 0);
            }
          };
  
          var isRunning = (Howler.state === 'running');
          if (self._state === 'loaded' && isRunning) {
            playWebAudio();
          } else {
            // Wait for the audio to load and then begin playback.
            self.once(isRunning ? 'load' : 'resume', playWebAudio, isRunning ? sound._id : null);
  
            // Cancel the end timer.
            self._clearTimer(sound._id);
          }
        } else {
          // Fire this when the sound is ready to play to begin HTML5 Audio playback.
          var playHtml5 = function() {
            node.currentTime = seek;
            node.volume = sound._volume * Howler.volume();
  
            setTimeout(function() {
              node.play();
  
              // Setup the new end timer.
              if (timeout !== Infinity) {
                self._endTimers[sound._id] = setTimeout(self._ended.bind(self, sound), timeout);
              }
  
              if (!internal) {
                self._emit('play', sound._id);
              }
            }, 0);
          };
  
          // Play immediately if ready, or wait for the 'canplaythrough'e vent.
          var loadedNoReadyState = (self._state === 'loaded' && (window && window.ejecta || !node.readyState && Howler._navigator.isCocoonJS));
          if (node.readyState === 4 || loadedNoReadyState) {
            playHtml5();
          } else {
            var listener = function() {
              // Begin playback.
              playHtml5();
  
              // Clear this listener.
              node.removeEventListener(Howler._canPlayEvent, listener, false);
            };
            node.addEventListener(Howler._canPlayEvent, listener, false);
  
            // Cancel the end timer.
            self._clearTimer(sound._id);
          }
        }
  
        return sound._id;
      },
  
      /**
       * Stop playback and reset to start.
       * @param  {Number} id The sound ID (empty to stop all in group).
       * @param  {Boolean} internal Internal Use: true prevents event firing.
       * @return {Howl}
       */
      stop: function(id, internal) {
        var self = this;
  
        // If the sound hasn't loaded, add it to the load queue to stop when capable.
        if (self._state !== 'loaded') {
          self._queue.push({
            event: 'stop',
            action: function() {
              self.stop(id);
            }
          });
  
          return self;
        }
  
        // If no id is passed, get all ID's to be stopped.
        var ids = self._getSoundIds(id);
  
        for (var i=0; i<ids.length; i++) {
          // Clear the end timer.
          self._clearTimer(ids[i]);
  
          // Get the sound.
          var sound = self._soundById(ids[i]);
  
          if (sound) {
            sound._ended = true;
  
            if (sound._node) {
              if (self._webAudio) {
                // make sure the sound has been created
                if (!sound._node.bufferSource) {
                  if (!internal) {
                    self._emit('stop', sound._id);
                  }
  
                  return self;
                }
  
                if (typeof sound._node.bufferSource.stop === 'undefined') {
                  sound._node.bufferSource.noteOff(0);
                } else {
                  sound._node.bufferSource.stop(0);
                }
  
                // Clean up the buffer source.
                self._cleanBuffer(sound._node);
              } else if (!isNaN(sound._node.duration) || sound._node.duration === Infinity) {
                sound._node.currentTime = sound._start || 0;
                sound._node.pause();
              }
            }
          }
  
          if (sound && !internal) {
            self._emit('stop', sound._id);
          }
        }
  
        return self;
      },
  
      /**
       * Get/set the volume of this sound or of the Howl group. This method can optionally take 0, 1 or 2 arguments.
       *   volume() -> Returns the group's volume value.
       *   volume(id) -> Returns the sound id's current volume.
       *   volume(vol) -> Sets the volume of all sounds in this Howl group.
       *   volume(vol, id) -> Sets the volume of passed sound id.
       * @return {Howl/Number} Returns self or current volume.
       */
      volume: function() {
        var self = this;
        var args = arguments;
        var vol, id;
  
        // Determine the values based on arguments.
        if (args.length === 0) {
          // Return the value of the groups' volume.
          return self._volume;
        } else if (args.length === 1 || args.length === 2 && typeof args[1] === 'undefined') {
          // First check if this is an ID, and if not, assume it is a new volume.
          var ids = self._getSoundIds();
          var index = ids.indexOf(args[0]);
          if (index >= 0) {
            id = parseInt(args[0], 10);
          } else {
            vol = parseFloat(args[0]);
          }
        } else if (args.length >= 2) {
          vol = parseFloat(args[0]);
          id = parseInt(args[1], 10);
        }
  
        // Update the volume or return the current volume.
        var sound;
        if (typeof vol !== 'undefined' && vol >= 0 && vol <= 1) {
          // If the sound hasn't loaded, add it to the load queue to change volume when capable.
          if (self._state !== 'loaded') {
            self._queue.push({
              event: 'volume',
              action: function() {
                self.volume.apply(self, args);
              }
            });
  
            return self;
          }
  
          // Set the group volume.
          if (typeof id === 'undefined') {
            self._volume = vol;
          }
  
          // Update one or all volumes.
          id = self._getSoundIds(id);
          for (var i=0; i<id.length; i++) {
            // Get the sound.
            sound = self._soundById(id[i]);
  
            if (sound) {
              sound._volume = vol;
  
              if (self._webAudio && sound._node) {
                sound._node.gain.setValueAtTime(vol, Howler.ctx.currentTime);
              } else if (sound._node) {
                sound._node.volume = vol * Howler.volume();
              }
  
              self._emit('volume', sound._id);
            }
          }
        } else {
          sound = id ? self._soundById(id) : self._sounds[0];
          return sound ? sound._volume : 0;
        }
  
        return self;
      },
  
      /**
       * Check if a specific sound is currently playing or not (if id is provided), or check if at least one of the sounds in the group is playing or not.
       * @param  {Number}  id The sound id to check. If none is passed, the whole sound group is checked.
       * @return {Boolean} True if playing and false if not.
       */
      playing: function(id) {
        var self = this;
  
        // Check the passed sound ID (if any).
        if (typeof id === 'number') {
          return !!self._soundById(id);
        }
  
        // Otherwise, loop through all sounds and check if any are playing.
        return self._sounds.length > 0;
      },
  
      /**
       * Get the duration of this sound. Passing a sound id will return the sprite duration.
       * @param  {Number} id The sound id to check. If none is passed, return full source duration.
       * @return {Number} Audio duration in seconds.
       */
      duration: function(id) {
        var self = this;
        var duration = self._duration;
  
        // If we pass an ID, get the sound and return the sprite length.
        var sound = self._soundById(id);
        if (sound) {
          duration = self._sprite[1] / 1000;
        }
  
        return duration;
      },
  
      /**
       * Returns the current loaded state of this Howl.
       * @return {String} 'unloaded', 'loading', 'loaded'
       */
      state: function() {
        return this._state;
      },
  
      /**
       * Unload and destroy the current Howl object.
       * This will immediately stop all sound instances attached to this group.
       */
      unload: function() {
        var self = this;
  
        // Stop playing any active sounds.
        var sounds = self._sounds;
        for (var i=0; i<sounds.length; i++) {
          // Stop the sound if it is currently playing.
          self.stop(sounds[i]._id);
  
          // Remove the source or disconnect.
          if (!self._webAudio) {
            // Set the source to 0-second silence to stop any downloading.
            sounds[i]._node.src = 'data:audio/wav;base64,UklGRiQAAABXQVZFZm10IBAAAAABAAEARKwAAIhYAQACABAAZGF0YQAAAAA=';
  
            // Remove any event listeners.
            sounds[i]._node.removeEventListener('error', sounds[i]._errorFn, false);
            sounds[i]._node.removeEventListener(Howler._canPlayEvent, sounds[i]._loadFn, false);
          }
  
          // Empty out all of the nodes.
          delete sounds[i]._node;
  
          // Make sure all timers are cleared out.
          self._clearTimer(sounds[i]._id);
  
          // Remove the references in the global Howler object.
          var index = Howler._howls.indexOf(self);
          if (index >= 0) {
            Howler._howls.splice(index, 1);
          }
        }
  
        // Delete this sound from the cache (if no other Howl is using it).
        var remCache = true;
        for (i=0; i<Howler._howls.length; i++) {
          if (Howler._howls[i]._src === self._src) {
            remCache = false;
            break;
          }
        }
  
        if (cache && remCache) {
          delete cache[self._src];
        }
  
        // Clear global errors.
        Howler.noAudio = false;
  
        // Clear out `self`.
        self._state = 'unloaded';
        self._sounds = [];
        self = null;
  
        return null;
      },
  
      /**
       * Listen to a custom event.
       * @param  {String}   event Event name.
       * @param  {Function} fn    Listener to call.
       * @param  {Number}   id    (optional) Only listen to events for this sound.
       * @param  {Number}   once  (INTERNAL) Marks event to fire only once.
       * @return {Howl}
       */
      on: function(event, fn, id, once) {
        var self = this;
        var events = self['_on' + event];
  
        if (typeof fn === 'function') {
          events.push(once ? {id: id, fn: fn, once: once} : {id: id, fn: fn});
        }
  
        return self;
      },
  
      /**
       * Remove a custom event. Call without parameters to remove all events.
       * @param  {String}   event Event name.
       * @param  {Function} fn    Listener to remove. Leave empty to remove all.
       * @param  {Number}   id    (optional) Only remove events for this sound.
       * @return {Howl}
       */
      off: function(event, fn, id) {
        var self = this;
        var events = self['_on' + event];
        var i = 0;
  
        if (fn) {
          // Loop through event store and remove the passed function.
          for (i=0; i<events.length; i++) {
            if (fn === events[i].fn && id === events[i].id) {
              events.splice(i, 1);
              break;
            }
          }
        } else if (event) {
          // Clear out all events of this type.
          self['_on' + event] = [];
        } else {
          // Clear out all events of every type.
          var keys = Object.keys(self);
          for (i=0; i<keys.length; i++) {
            if ((keys[i].indexOf('_on') === 0) && Array.isArray(self[keys[i]])) {
              self[keys[i]] = [];
            }
          }
        }
  
        return self;
      },
  
      /**
       * Listen to a custom event and remove it once fired.
       * @param  {String}   event Event name.
       * @param  {Function} fn    Listener to call.
       * @param  {Number}   id    (optional) Only listen to events for this sound.
       * @return {Howl}
       */
      once: function(event, fn, id) {
        var self = this;
  
        // Setup the event listener.
        self.on(event, fn, id, 1);
  
        return self;
      },
  
      /**
       * Emit all events of a specific type and pass the sound id.
       * @param  {String} event Event name.
       * @param  {Number} id    Sound ID.
       * @param  {Number} msg   Message to go with event.
       * @return {Howl}
       */
      _emit: function(event, id, msg) {
        var self = this;
        var events = self['_on' + event];
  
        // Loop through event store and fire all functions.
        for (var i=events.length-1; i>=0; i--) {
          if (!events[i].id || events[i].id === id || event === 'load') {
            setTimeout(function(fn) {
              fn.call(this, id, msg);
            }.bind(self, events[i].fn), 0);
  
            // If this event was setup with `once`, remove it.
            if (events[i].once) {
              self.off(event, events[i].fn, events[i].id);
            }
          }
        }
  
        return self;
      },
  
      /**
       * Queue of actions initiated before the sound has loaded.
       * These will be called in sequence, with the next only firing
       * after the previous has finished executing (even if async like play).
       * @return {Howl}
       */
      _loadQueue: function() {
        var self = this;
  
        if (self._queue.length > 0) {
          var task = self._queue[0];
  
          // don't move onto the next task until this one is done
          self.once(task.event, function() {
            self._queue.shift();
            self._loadQueue();
          });
  
          task.action();
        }
  
        return self;
      },
  
      /**
       * Fired when playback ends at the end of the duration.
       * @param  {Sound} sound The sound object to work with.
       * @return {Howl}
       */
      _ended: function(sound) {
        var self = this;
  
        // Fire the ended event.
        self._emit('end', sound._id);
  
        // Mark the node as paused.
        if (self._webAudio) {
          sound._ended = true;
          self._clearTimer(sound._id);
  
          // Clean up the buffer source.
          self._cleanBuffer(sound._node);
  
          // Attempt to auto-suspend AudioContext if no sounds are still playing.
          Howler._autoSuspend();
        }
  
        // When using a sprite, end the track.
        if (!self._webAudio) {
          self.stop(sound._id);
        }
  
        return self;
      },
  
      /**
       * Clear the end timer for a sound playback.
       * @param  {Number} id The sound ID.
       * @return {Howl}
       */
      _clearTimer: function(id) {
        var self = this;
  
        if (self._endTimers[id]) {
          clearTimeout(self._endTimers[id]);
          delete self._endTimers[id];
        }
  
        return self;
      },
  
      /**
       * Return the sound identified by this ID, or return null.
       * @param  {Number} id Sound ID
       * @return {Object}    Sound object or null.
       */
      _soundById: function(id) {
        var self = this;
  
        // Loop through all sounds and find the one with this ID.
        for (var i=0; i<self._sounds.length; i++) {
          if (id === self._sounds[i]._id) {
            return self._sounds[i];
          }
        }
  
        return null;
      },
  
      /**
       * Return an inactive sound from the pool or create a new one.
       * @return {Sound} Sound playback object.
       */
      _inactiveSound: function() {
        var self = this;
  
        self._drain();
  
        // Find the first inactive node to recycle.
        for (var i=0; i<self._sounds.length; i++) {
          if (self._sounds[i]._ended) {
            return self._sounds[i].reset();
          }
        }
  
        // If no inactive node was found, create a new one.
        return new Sound(self);
      },
  
      /**
       * Drain excess inactive sounds from the pool.
       */
      _drain: function() {
        var self = this;
        var limit = self._pool;
        var cnt = 0;
        var i = 0;
  
        // If there are less sounds than the max pool size, we are done.
        if (self._sounds.length < limit) {
          return;
        }
  
        // Count the number of inactive sounds.
        for (i=0; i<self._sounds.length; i++) {
          if (self._sounds[i]._ended) {
            cnt++;
          }
        }
  
        // Remove excess inactive sounds, going in reverse order.
        for (i=self._sounds.length - 1; i>=0; i--) {
          if (cnt <= limit) {
            return;
          }
  
          if (self._sounds[i]._ended) {
            // Disconnect the audio source when using Web Audio.
            if (self._webAudio && self._sounds[i]._node) {
              self._sounds[i]._node.disconnect(0);
            }
  
            // Remove sounds until we have the pool size.
            self._sounds.splice(i, 1);
            cnt--;
          }
        }
      },
  
      /**
       * Get all ID's from the sounds pool.
       * @param  {Number} id Only return one ID if one is passed.
       * @return {Array}    Array of IDs.
       */
      _getSoundIds: function(id) {
        var self = this;
  
        if (typeof id === 'undefined') {
          var ids = [];
          for (var i=0; i<self._sounds.length; i++) {
            ids.push(self._sounds[i]._id);
          }
  
          return ids;
        } else {
          return [id];
        }
      },
  
      /**
       * Load the sound back into the buffer source.
       * @param  {Sound} sound The sound object to work with.
       * @return {Howl}
       */
      _refreshBuffer: function(sound) {
        var self = this;
  
        // Setup the buffer source for playback.
        sound._node.bufferSource = Howler.ctx.createBufferSource();
        sound._node.bufferSource.buffer = cache[self._src];
  
        // Connect to the correct node.
        if (sound._panner) {
          sound._node.bufferSource.connect(sound._panner);
        } else {
          sound._node.bufferSource.connect(sound._node);
        }
  
        return self;
      },
  
      /**
       * Prevent memory leaks by cleaning up the buffer source after playback.
       * @param  {Object} node Sound's audio node containing the buffer source.
       * @return {Howl}
       */
      _cleanBuffer: function(node) {
        var self = this;
  
        if (self._scratchBuffer) {
          node.bufferSource.onended = null;
          node.bufferSource.disconnect(0);
          try { node.bufferSource.buffer = self._scratchBuffer; } catch(e) {}
        }
        node.bufferSource = null;
  
        return self;
      }
    };
  
    /** Single Sound Methods **/
    /***************************************************************************/
  
    /**
     * Setup the sound object, which each node attached to a Howl group is contained in.
     * @param {Object} howl The Howl parent group.
     */
    var Sound = function(howl) {
      this._parent = howl;
      this.init();
    };
    Sound.prototype = {
      /**
       * Initialize a new Sound object.
       * @return {Sound}
       */
      init: function() {
        var self = this;
        var parent = self._parent;
  
        // Setup the default parameters.
        self._volume = parent._volume;
        self._ended = true;
  
        // Generate a unique ID for this sound.
        self._id = Math.round(Date.now() * Math.random());
  
        // Add itself to the parent's pool.
        parent._sounds.push(self);
  
        // Create the new node.
        self.create();
  
        return self;
      },
  
      /**
       * Create and setup a new sound object, whether HTML5 Audio or Web Audio.
       * @return {Sound}
       */
      create: function() {
        var self = this;
        var parent = self._parent;
        var volume = self._volume;
  
        if (parent._webAudio) {
          // Create the gain node for controlling volume (the source will connect to this).
          self._node = (typeof Howler.ctx.createGain === 'undefined') ? Howler.ctx.createGainNode() : Howler.ctx.createGain();
          self._node.gain.setValueAtTime(volume, Howler.ctx.currentTime);
          self._node.connect(Howler.masterGain);
        } else {
          self._node = new Audio();
  
          // Listen for errors (http://dev.w3.org/html5/spec-author-view/spec.html#mediaerror).
          self._errorFn = self._errorListener.bind(self);
          self._node.addEventListener('error', self._errorFn, false);
  
          // Listen for 'canplaythrough' event to let us know the sound is ready.
          self._loadFn = self._loadListener.bind(self);
          self._node.addEventListener(Howler._canPlayEvent, self._loadFn, false);
  
          // Setup the new audio node.
          self._node.src = parent._src;
          self._node.preload = 'auto';
          self._node.volume = volume * Howler.volume();
  
          // Begin loading the source.
          self._node.load();
        }
  
        return self;
      },
  
      /**
       * Reset the parameters of this sound to the original state (for recycle).
       * @return {Sound}
       */
      reset: function() {
        var self = this;
        var parent = self._parent;
  
        // Reset all of the parameters of this sound.
        self._volume = parent._volume;
        self._ended = true;
  
        // Generate a new ID so that it isn't confused with the previous sound.
        self._id = Math.round(Date.now() * Math.random());
  
        return self;
      },
  
      /**
       * HTML5 Audio error listener callback.
       */
      _errorListener: function() {
        var self = this;
  
        // Fire an error event and pass back the code.
        self._parent._emit('loaderror', self._id, self._node.error ? self._node.error.code : 0);
  
        // Clear the event listener.
        self._node.removeEventListener('error', self._errorListener, false);
      },
  
      /**
       * HTML5 Audio canplaythrough listener callback.
       */
      _loadListener: function() {
        var self = this;
        var parent = self._parent;
  
        // Round up the duration to account for the lower precision in HTML5 Audio.
        parent._duration = Math.ceil(self._node.duration * 10) / 10;
  
        // Setup a sprite if none is defined.
        if (!parent._sprite) {
          parent._sprite = [0, parent._duration * 1000];
        }
  
        if (parent._state !== 'loaded') {
          parent._state = 'loaded';
          parent._emit('load');
          parent._loadQueue();
        }
  
        // Clear the event listener.
        self._node.removeEventListener(Howler._canPlayEvent, self._loadFn, false);
      }
    };
  
    /** Helper Methods **/
    /***************************************************************************/
  
    var cache = {};
  
    /**
     * Buffer a sound from URL, Data URI or cache and decode to audio source (Web Audio API).
     * @param  {Howl} self
     */
    var loadBuffer = function(self) {
      var url = self._src;
  
      // Check if the buffer has already been cached and use it instead.
      if (cache[url]) {
        // Set the duration from the cache.
        self._duration = cache[url].duration;
  
        // Load the sound into this Howl.
        loadSound(self);
  
        return;
      }
  
      if (/^data:[^;]+;base64,/.test(url)) {
        // Decode the base64 data URI without XHR, since some browsers don't support it.
        var data = atob(url.split(',')[1]);
        var dataView = new Uint8Array(data.length);
        for (var i=0; i<data.length; ++i) {
          dataView[i] = data.charCodeAt(i);
        }
  
        decodeAudioData(dataView.buffer, self);
      } else {
        // Load the buffer from the URL.
        var xhr = new XMLHttpRequest();
        xhr.open('GET', url, true);
        xhr.responseType = 'arraybuffer';
        xhr.onload = function() {
          // Make sure we get a successful response back.
          var code = (xhr.status + '')[0];
          if (code !== '0' && code !== '2' && code !== '3') {
            self._emit('loaderror', null, 'Failed loading audio file with status: ' + xhr.status + '.');
            return;
          }
  
          decodeAudioData(xhr.response, self);
        };
        xhr.onerror = function() {
          // If there is an error, switch to HTML5 Audio.
          if (self._webAudio) {
            self._html5 = true;
            self._webAudio = false;
            self._sounds = [];
            delete cache[url];
            self.load();
          }
        };
        safeXhrSend(xhr);
      }
    };
  
    /**
     * Send the XHR request wrapped in a try/catch.
     * @param  {Object} xhr XHR to send.
     */
    var safeXhrSend = function(xhr) {
      try {
        xhr.send();
      } catch (e) {
        xhr.onerror();
      }
    };
  
    /**
     * Decode audio data from an array buffer.
     * @param  {ArrayBuffer} arraybuffer The audio data.
     * @param  {Howl}        self
     */
    var decodeAudioData = function(arraybuffer, self) {
      // Decode the buffer into an audio source.
      Howler.ctx.decodeAudioData(arraybuffer, function(buffer) {
        if (buffer && self._sounds.length > 0) {
          cache[self._src] = buffer;
          loadSound(self, buffer);
        }
      }, function() {
        self._emit('loaderror', null, 'Decoding audio data failed.');
      });
    };
  
    /**
     * Sound is now loaded, so finish setting everything up and fire the loaded event.
     * @param  {Howl} self
     * @param  {Object} buffer The decoded buffer sound source.
     */
    var loadSound = function(self, buffer) {
      // Set the duration.
      if (buffer && !self._duration) {
        self._duration = buffer.duration;
      }
  
      // Setup a sprite if none is defined.
      if (!self._sprite) {
        self._sprite = [0, self._duration * 1000];
      }
  
      // Fire the loaded event.
      if (self._state !== 'loaded') {
        self._state = 'loaded';
        self._emit('load');
        self._loadQueue();
      }
    };
  
    /**
     * Setup the audio context when available, or switch to HTML5 Audio mode.
     */
    var setupAudioContext = function() {
      // Check if we are using Web Audio and setup the AudioContext if we are.
      try {
        if (typeof AudioContext !== 'undefined') {
          Howler.ctx = new AudioContext();
        } else if (typeof webkitAudioContext !== 'undefined') {
          Howler.ctx = new webkitAudioContext();
        } else {
          Howler.usingWebAudio = false;
        }
      } catch(e) {
        Howler.usingWebAudio = false;
      }
  
      // Check if a webview is being used on iOS8 or earlier (rather than the browser).
      // If it is, disable Web Audio as it causes crashing.
      var iOS = (/iP(hone|od|ad)/.test(Howler._navigator && Howler._navigator.platform));
      var appVersion = Howler._navigator && Howler._navigator.appVersion.match(/OS (\d+)_(\d+)_?(\d+)?/);
      var version = appVersion ? parseInt(appVersion[1], 10) : null;
      if (iOS && version && version < 9) {
        var safari = /safari/.test(Howler._navigator && Howler._navigator.userAgent.toLowerCase());
        if (Howler._navigator && Howler._navigator.standalone && !safari || Howler._navigator && !Howler._navigator.standalone && !safari) {
          Howler.usingWebAudio = false;
        }
      }
  
      // Create and expose the master GainNode when using Web Audio (useful for plugins or advanced usage).
      if (Howler.usingWebAudio) {
        Howler.masterGain = (typeof Howler.ctx.createGain === 'undefined') ? Howler.ctx.createGainNode() : Howler.ctx.createGain();
        Howler.masterGain.gain.value = 1;
        Howler.masterGain.connect(Howler.ctx.destination);
      }
  
      // Re-run the setup on Howler.
      Howler._setup();
    };
  
    window.HowlerGlobal = HowlerGlobal;
    window.Howler = Howler;
    window.Howl = Howl;
    window.Sound = Sound;
  })();
  