message: only set the stop when it's not synced
  otherwise it reschedules multiple stops
diff: @@ -160,8 +160,8 @@ define(["../core/Tone", "../core/Buffer", "../source/Source", "../source/TickSou
  Tone.Player.prototype._onSourceEnd = function(source){
  var index = this._activeSources.indexOf(source);
  this._activeSources.splice(index, 1);
  - if (this._activeSources.length === 0){
  - this.stop();
  + if (this._activeSources.length === 0 && !this._synced){
  + this._state.setStateAtTime(Tone.State.Stopped, Tone.now());
  }
  };
  