Audio

If you put a Touch component on a scene object, with a reference to a mesh visual to tap on, then add an Audio object to the scene with your audio file referenced in the inspector, you could do something like: 

//@input Component.AudioComponent audio

var soundPlaying = false;

function onTap(eventData) {

  // if you're not looping the sound, you need a check to see if
  // it finished playing so you can set boolean back to false:
  if (!script.audio.isPlaying() && soundPlaying == true) {
      soundPlaying = false;
  }

  if (!soundPlaying) {
    soundPlaying = true;
    script.audio.play(-1);  
    // (-1) loops, use (1) if you want it to only play once
  } else {
    soundPlaying = false;
    script.audio.stop(false); // false means no fade-out
  }
}

var tapEvent = script.createEvent("TouchStartEvent");
tapEvent.bind(onTap);

Hello, Michael French. Thank you very much, I will try it!