Hi John
Yes - putting the script in the header of the module was my first approach. Off to try the page header now - Doh!
Does Js have any reference to the event queue controller as I am one of those currently commenting this out to side step the AppPool identity issue ?
http://dotnetnuke.com/Community/ForumsDotNetNuke/tabid/795/forumid/107/threadid/47749/scope/posts/Default.aspx
By the way Thanks for PageBlaster.

I also tried this - (works loaded as an html fragment inside an aspx page on a non dnn site) - included in case its useful to others who need multiple media files but only one player.
I would really like to know why this does not work.

<OBJECT ID="Player" height="300" width="400"
  CLASSID="CLSID:6BF52A52-394A-11d3-B153-00C04F79FAA6">
</OBJECT>
<br>
Clip 1&nbsp;
<INPUT TYPE=  "Button" NAME="BtnPlay" VALUE="Play" OnClick="StartMeUp()">
<SCRIPT>
<!--
function StartMeUp ()
{ Player.URL = "http://www.hopeitworks.co.uk/portals/0/video/mpower_edit 1.wmv";}
-->
</SCRIPT>
<p>Clip 2&nbsp;
<INPUT TYPE="BUTTON" NAME="BtnPlay1" VALUE="Play" OnClick="StartMeUp()">
<SCRIPT>
<!--
function StartMeUp ()
{ Player.URL = "http://www.hopeitworks.co.uk/portals/0/video/mpower_edit 2.wmv";}
-->
</SCRIPT>
</p>

Thanks