as in an older message from 2004 I have the same problem. I have downloaded, I guess, an avi with bad audio. I'm trying to stream the audio of it with virtualdubmod, because tmpgenc 2.5 doesn't see the audio. with an avi audio decompressor i get the message: could not render audio stream. so i wanted to try it with virtualdubmod, but then i fot this message like in this topic: http://forums.afterdawn.com/thread_view.cfm/125180 my problem starts early. after setting audio on full expressing mode i got the message that i don't have the right codec installed to do this. If I set the audio at direct stream copy it works. I absolutely have no idea which codec i need. can some one please help me?