function position(sound_name, x, y, z, id) {
	const sound = audioTracks[sound_name];
	if (sound && typeof sound !== "undefined") {
		return sound.pos(x, y, z, id);
	} else {
		throw new Error("audio clip " + sound_name + " does not exist");
	}
}
get or set the 3D spatial position for the specified sound.
@param {string} sound_name - audio clip name - case sensitive
@param  {Number} x - the x-position of the audio source.
@param  {Number} y - the y-position of the audio source.
@param  {Number} z - the z-position of the audio source.
@param {number} [id] - the sound instance ID. If none is passed, all sounds in group will be changed.
@return {Array} the current 3D spatial position: [x, y, z]