Loading sound through xml problem

1

I’m having a problem making my audio start playing automatically, i can get it start once it has loaded but it seems to play several instances of the audio loop and bogs down the system and evetually crashes, the only way it wokrs fine is if the user is to start it manually by cliking the audio button then it plays fine?

Heres the actionscript:

function loadXML(loaded) { 
    if (loaded) { 
        bgImg = this.firstChild.childNodes[0].firstChild.nodeValue;
        loopBg = this.firstChild.childNodes[1].firstChild.nodeValue;
        _root.background_img._alpha = 0;
        _root.background_img.loadMovie(bgImg, 1);
        _root.loopSound = new Sound();
        _root.loopSound.loadSound(loopBg, false);
        _root.loopSound.start();
    } else { 
          trace("file not loaded!"); 
    } 
}

xmlData = new XML(); 
xmlData.ignoreWhite = true; 
xmlData.onLoad = loadXML; 
xmlData.load("xml/background.xml"); 

//Preloads image using movieclip loader instance
this.onEnterFrame = function() { 
    size = _root.background_img.getBytesTotal() + _root.loopSound.getBytesTotal();
    loaded = _root.background_img.getBytesLoaded() + _root.loopSound.getBytesLoaded();
    preloader._visible = true; 
        if (loaded != size) { 
            preloader.bar._xscale = 100*loaded/size;
        } else { 
            preloader._visible = false;
            _root.loopSound.start();
        // fades in image
        if (_root.background_img._alpha<100) { 
            _root.background_img._alpha += 10;
            }
        } 
}
stop();

I have the xml file load a background image and the background audio, how can I get the audio to play automatically without it playing several instances of itself and crashing?

Cheers,
Inept