soundClip = new Sound();
soundClip.load(new URLRequest("path"));
soundClip.addEventListener(Event.COMPLETE, soundLoaded);
soundClip.addEventListener(ProgressEvent.PROGRESS, soundLoading);
function soundLoaded(e:Event) {
soundClip.play();
}
function soundLoading(e:Event) {
//do something else
}
это похоже на видеоклип.