It'd help us help you if we could see your profile, or if you at least told us whether your profile is Current or Classic (different code for different profile types). The problem may be that if you use visibility:hidden to make a media panel hidden, it won't actually play on some browsers. The options that we're left with are mostly quite stupid code-wise, but then again so is hidden media in general. Not everyone may share your music taste, so if your media is hidden people may just immediately leave your profile to get away from the music that they can't pause.
If you still want to hide it anyway, try this instead (as in remove that code and put this in).