Shoutbox

I'm having a problem with firefox and i thought maybe one of you guys know how to solve this.

Firefox just doesn't want to play a video when it uses the WMP(10) plugin.
The video doesn't autoplay and when I press the play button, nothing happens except that the button gets grayed out and then goes back to being enabled.
This doens't happen when an embed-tag uses the quicktime plugin.

Does anyone know how to solve this problem or an alternative? Thanks.