ActionScript 3.0 :: MP3 Player - Getting Error When Not Viewed Locally

I am a as3 nub but basically when I view locally I have no issues... When I view over a network I get an error like:
TypeError: Error #1009: Cannot access a property or method of a null object reference.

I am calling this mp3 player from inside another movie...
PHP Code:
var xmlLoader:URLLoader = new URLLoader();
xmlLoader.addEventListener(Event.COMPLETE, showXML);
xmlLoader.load(new URLRequest("playlist.xml"));
var trackList:Array = [];
var bandList:Array = [];
var fileList:Array = [];
var MusicLoading:URLRequest;//File Request
[Code] .....