I can't see where your doing anything wrong with the coding that would prevent it from playing. Most likely they don't have the MIME types set up on the server for sound files.
When posting a wav file to a message board
1. you NEVER want to use Autoplay unless you warn them in the subject line beforehand, otherwise people with slower connections could be trapped.
2. You never want to hide the control panel (whether you use autoplay or not) so anyone irritated by your wave file or if your wave file is slowing down their computer can shut it off.
3. NEVER use the Loop property unless it's set to FALSE. If I ran unsuspectingly into a wave file that I couldnt turn off and looped endlessly I'd kill you.
Well, first I'd turn my speakers down, THEN I'd kill you.
~ Raven ~