probleme de lecture d'un fichier mp3 avec XML

Code:
<Liste>
<Music URL="1.mp3">titre</Music>
<Music URL="C:\1.mp3">music1</Music>
</Liste> 

var listeXML:XML = new XML();
listeXML.ignoreWhite = true;
var music:Sound = new Sound();
var musicencour:String;
listeXML.onLoad = function(){
var tempArray = new Array();
for(var i = 0; i < this.firstChild.childNodes.length; ++i){
tempArray[i] = new Object();
tempArray[i].label = this.firstChild.childNodes[i].firstChild.nodeValue;
tempArray[i].data = this.firstChild.childNodes[i].attributes.URL;
}
liste_lb.dataProvider = tempArray;
}
listeXML.load("liste.xml");
var liste_lbListener:Object = new Object();
liste_lbListener.change = function(){
musicencour = liste_lb.selectedItem.data;
}
liste_lb.addEventListener("change", liste_lbListener);
lecture_btn.onRelease = function(){
music.stop();
music = new Sound();
music.onID3 = function(){
music_txt.text = this.id3.TIT2;
artiste_txt.text = this.id3.TPE1;
annee_txt.text = this.id3.TYER;
URL_txt.htmlText = "<a href=\"" + this.id3.WXXX + "\">" + this.id3.WXXX + "</a>";
commentaire_txt.text = this.id3.COMM;
}
music.loadSound(musicencour, true);
}
stop_btn.onRelease = function(){
music.stop();
}