How do I write a halt script vs an onComplete script?

I am having an issue with a swf playing over another swf.  The stop audio portion of my ActionScript is occurring onComplete rather then a halt script action.  This was not a problen when I tested locally since the files would download in 1 or 2 seconds instead of 8 to 12 seconds.   Can someone tell me how to change the onComplete to a halt action?  My script is below.

//run at once

var sRequest:URLRequest = new URLRequest("track01.swf");
var externalMovie:MovieClip;

var swfLoader:Loader = new Loader();
swfLoader.load(sRequest);
this.addChild(swfLoader);

swfLoader.contentLoaderInfo.addEventListener(Event.COMPLETE, onComplete);

function onComplete(evtObj:Event):void{

  externalMovie = MovieClip(swfLoader.content)
 
}

//------------------button code

this.addEventListener(MouseEvent.CLICK, onClick);

function onClick(evtObj:MouseEvent):void{

externalMovie.stop();

//this.removeChild(swfLoader);
//trace(evtObj.target.name)

var buttonClicked:String = evtObj.target.name;

swfLoader.load(new URLRequest(buttonClicked + ".swf"));

}