SMTCevents.js

if (typeof Windows !== 'undefined') {
  var systemMediaControls = Windows.Media.SystemMediaTransportControls.getForCurrentView();
  systemMediaControls.addEventListener("buttonpressed", systemMediaControlsButtonPressed, false);
  systemMediaControls.isPlayEnabled = true;
  systemMediaControls.isPauseEnabled = true;
  systemMediaControls.isStopEnabled = true;

  systemMediaControls.playbackStatus = Windows.Media.MediaPlaybackStatus.closed;
}