i've had the us-122 for about a year in a half and i've used it on windwos and i couldnt be happier with it, recently i just switched to mac i have a powerbook g4 with osx the tascam hardware installed just fine tho cubasis didnt b/c of osx but i didnt really care b/c of garageband well now thats where im having trouble, i set the input in garageband to the us-122 and even messed with the output im not gettin a response from either,so i opened up the us-122 manager and im not getting a response from that either, yes my usb cord is plugged in and my input is a guitar, does somone know a secret that i dont to get this to work?

The problem appears to be that US122 is incompatable w/ OS X Tiger. Check out the discussion at This thread from a few days ago.