In the below code i get an error saying Error #2007: Parameter url must be non-null on Ineternet explorer only.What am i doing wrong here

html

  <OBJECT
                                     classid="clsid:D27CDB6E-AE6D-11cf-96B8-444553540000"
                                     WIDTH="50"
                                     HEIGHT="50"
                                     id="myMovieName">

                                   <PARAM NAME="movie" VALUE="/media/players/testsound.swf" />
                                   <PARAM NAME="quality" VALUE="high" />
                                   <PARAM NAME="bgcolor" VALUE="#FFFFFF" />

                                   <EMBED
                                      href="/media/players/testsound.swf"
             src="/media/players/testsound.swf"
             flashvars="soundUrl=sound.mp3"
                                      quality=high
                                      bgcolor=#FFFFFF
                                      NAME="myMovieName"
                                      ALIGN=""
                                      TYPE="application/x-shockwave-flash">
                                   </EMBED>
                                   </OBJECT>

mxml ; import flash.net.; import mx.controls.Alert; import mx.controls.Button; import flash.events.Event; import flash.media.Sound; import flash.net.URLRequest;

private function clickhandler(event:Event):void
     {
        var musicfile:String;
        var s:Sound = new Sound();
        s.addEventListener(Event.COMPLETE, onSoundLoaded);
        var req:URLRequest = new URLRequest("/opt/cloodon/site/media/players/sound.mp3");
        //musicfile = stage.loaderInfo.parameters["soundUrl"];
        //var req:URLRequest = new URLRequest(musicfile);
        s.load(req);

     }

     private function onSoundLoaded(event:Event):void
     {
        //Alert.show("1");
        //var localSound:Sound = event.currentTarget as Sound;
        var localSound:Sound = event.target as Sound;
        localSound.play();
     }

  ]]>
</fx:Script>
<fx:Declarations>
  <!-- Place non-visual elements (e.g., services, value objects) here -->
</fx:Declarations>
<!--<mx:Button id="play" label="PLAY" click="clickhandler(event)"  />-->
<mx:Image id="loader1" source="@Embed(source='/opt/cloodon/site/media/img/speaker.gif')" click="clickhandler(event)" />

</s:Application>