<html>
<head>
<script>
function start () {
  const context = new AudioContext();
  const {stream} = new MediaStreamAudioDestinationNode(context);
  const [track] = stream.getTracks();
  track.stop();
  context.createMediaStreamTrackSource(track);
}

document.addEventListener('DOMContentLoaded', start);
</script>
</head>
</html>
