Need help fast with audio fading

i need to have two audio file’s volume fade from 0 to 100 along the x axis, so that when one fades in, the other fades out, and reversed. heres to code i have now (that doesnt work):

mySound = new Sound();
mySound.attachSound(“music”);
mySound.start();

mySound2 = new Sound();
mySound2.attachSound(“music2”);
mySound2.start();

onEnterFrame = function(){
var volume = (_root._xmouse / Stage.width) * 100;
var volume2 = (100 - volume);

mySound.setVolume(volume);
mySound2.setVolume(volume2);
}

this isnt working (and it isnt identifier names), if someone can either fix that, or make a new script that does what i want that would be greatly appreciated. im totally stumped.