Document.WinMedia problem Firefox

I have added a Windows media Player to my page which plays a the Usher yeah Video. I have also hided all the controls. This is so that I could implement it with my own custom buttons. The code for the WinMedia object is here:

<object classid=“CLSID:22D6F312-B0F6-11D0-94AB-0080C74C7E95”
codebase=“http://activex.microsoft.com/activex/controls/
mplayer/en/nsmp2inf.cab#Version=5,1,52,701”
type=“application/x-oleobject” width=“361” height=“248” hspace=“0” vspace=“0” align=“middle” border=“0” standby=
“Loading Microsoft® Windows® Media Player components…” id=“WinMedia” style=“width: 361px; height: 248px”>
<param name=“FileName” value=“http://media.bmgonline.com/aristarec.com/usher/video/yeah_300.asx” />
<param name=“AutoStart” value=“True” />
<param name=“ShowAudioControls” value=“false” />
<param name=“ShowControls” value=“False” />
<param name=“ShowStatusBar” value=“True” />
<embed src=“http://media.bmgonline.com/aristarec.com/usher/video/yeah_300.asx” name="WinMedia"width=361 height=248 hspace=“0” vspace=“0” autostart=1 type=“application/x-mplayer2” pluginspage=“http://www.microsoft.com/Windows/MediaPlayer/” showstatusbar=“1” showcontrols=“0”></embed>
</object>

The code in I.E for making it stop playing is:

document.WinMedia.stop();

I have implemented this into a button:

<input type=“button” name=“Stop” onClick=“document.WinMedia.stop();” value=“Submit” />

This works perfectly in IE and I began to add other controls when I realised that it didn’t work in Firefox.

To give your more information.

document.getElementById(WinMedia).value returned WinMedia in IE, nothing in firefox

document.getElementByName(WinMedia).value returned WinMedia in Firefox, nothing in IE.

Please HELP!