I have a mac G5 running OS 10.3 and a Motu 828mkII firewire audio interface. Everything has worked fine until recently when something inexplicably stopped working. The MOTU firewire still pops up when the 828 is turned on so the firewire connection must be fine but i get no sound unless i revert to the built in audio. Also when i try to play a song in iTunes, the counter stays at 0:00 and nothing happens. When I Load up Logic Pro 6, I get a message saying: "Core Audio has returned error code 726". I have tried everything I can think of to no avail, even tried buying a new firewire cable and nothing has made any difference so far. Please can someone help and not refer my question to MOTU because I've tried everything they suggested already. Thanx