there's another thread about license errors, check for it. do you get audio in other games? I see that it's not an Iso problem but maybe there something else going on with your audio. I've heard of 1 or 2 other people having no audio and games and I don't know if they got a fix for it.
did you get your bios working? I've had issues in the past where when I tried to but my bios I got a license there but if I loaded it once or twice again it would work.