[Цветкофф]

var channel:SoundChannel = new SoundChannel();
var vol:SoundTransform = new SoundTransform(0, 0);
var sound:Sound = new Sound(new URLRequest(track_url));
 
var receiving_lc:LocalConnection = new LocalConnection();
receiving_lc.connect("lc_name");
receiving_lc.play_next = function():void
{
	channel = sound.play(0, 1, vol);
}
 
play_button.addEventListener (MouseEvent.MOUSE_DOWN, onPlayButton);
function onPlayButton (event:MouseEvent):void
{
	var sending_lc:LocalConnection = new LocalConnection();
	sending_lc.send("lc_name", "play_next");
}

не проверял, но на мой взгляд так должно работать