I have been looking for 7 hours for how to fix this problem with no avail. I have followed all possible solutions and been sent to the same site several times so I already knew that it wouldn't work Last night I downgraded from Vista to XP on my eMachine W3611 and I have not been able to get the sound to work. It just says 'No Audio Device" whenever I attempt something. I managed to get to the point where it recognizes "Microsoft UAA Bus Driver for High Definition Audio" and then I had a yellow "!" for.. Well, I forget what it said but the ending was something like 'for High Definition Bus' or something like that. After reinstalling the UAA Bus Driver what was once the 'for High Definition Bus' turned into Unknown Device. Any help would be greatly appreciated.