title: why does a web audio oscillator only play a note once?
body: <p>When I successfully create a tone with a Web Audio oscillator (with <code>noteOn</code>), then call its <code>noteOff</code> function, subsequent calls to <code>noteOn</code> doesn't play the tone again. I seem to have to create a new oscillator to play a new note. Why is this?</p>
  
  <pre><code>var ctx = new webkitAudioContext();
  var osc = ctx.createOscillator();
  osc.connect(ctx.destination);
  osc.start(0); // tone is heard (previously noteOn(0))
  
  // ... some time later
  osc.stop(0); // tone falls silent (previously noteOff(0))
  
  // ... some time later
  osc.start(0); // no effect! (previously noteOn(0))
  </code></pre>