title: Howler + ctx Analyser issue
body: <p>I'm trying to connect an audio analyzer node to my howler setup.</p>
  
  <p>The problem is that I get an array filled by "128" which mean there is no sound, but the sound is playing.</p>
  
  <p>Here is my code : </p>
  
  <pre><code>  var Sound = new Howl({
                src: 'https://ia802508.us.archive.org/5/items/testmp3testfile/mpthreetest.mp3',
                html5: true,
                format: ['mp3']
            });
  
    Sound.play();
  
    // Create analyzer
    var analyser = Howler.ctx.createAnalyser();
  
    // Connect master gain to analyzer
    Howler.masterGain.connect(analyser);
  
    // Connect analyzer to destination
    analyser.connect(Howler.ctx.destination);
  
    // Creating output array (according to documentation https://developer.mozilla.org/en-US/docs/Web/API/Web_Audio_API/Visualizations_with_Web_Audio_API)
    analyser.fftSize = 2048;
    var bufferLength = analyser.frequencyBinCount;
    var dataArray = new Uint8Array(bufferLength);
  
    // Get the Data array
    analyser.getByteTimeDomainData(dataArray);
  
    // Display array on time each 3 sec (just to debug)
    setInterval(function(){ 
      analyser.getByteTimeDomainData(dataArray);
      console.dir(dataArray);
    }, 3000);
  </code></pre>
  
  <p>Here is a plunker of my project reduced to minimal :</p>
  
  <p><a href="https://plnkr.co/edit/GlyWoo7qv1D059WF6g63" rel="nofollow noreferrer">Plunker</a></p>
  
  <p>My implementation  is based on these sources :</p>
  
  <p><a href="https://stackoverflow.com/questions/32460123/connect-analyzer-to-howler-sound">avanwink answer</a> on this post</p>
  
  <p><a href="https://developer.mozilla.org/en-US/docs/Web/API/Web_Audio_API/Visualizations_with_Web_Audio_API" rel="nofollow noreferrer">The documentation of sound visualization</a></p>