MovieClipLoader not loading in FF works in IE

programming flash
1

Not sure why, but my subSwf is not loading in FF, works in IE.

Any ideas appreciated.

var loader:MovieClipLoader = new MovieClipLoader();
var loadHandler:Object = new Object();
loader.addListener(loadHandler);
holder_mc._visible = false;
// define what should happen when the jpg/swf is completely loaded
// use _mc to refer to the loaded jpg/swf
loadHandler.onLoadInit = function(_mc:MovieClip) {
   _mc._visible = true;
   _mc._xscale = 100;
   _mc._yscale = 100;
   _mc.init();
};
 
// start loading specified jpg/swf into blank movieclip holder_mc on stage
loader.loadClip(_root.myPR.absolutePath + "myVideo.swf", holder_mc);