Hey im having a problem with my sound. Its not working and it seemed to have stopped working after the stupid service pack 3 update however when we tried to install service pack 3 for some reason it didnt install completely. It then rolled everything back and all of a sudden a week later the sound stopped working. I went into device manager and their were no ! next anything or x either. I then went and double clicked on VIA AC'97 Audio Controller (WDM) and went roll back drivers, it worked for a day and then went back to no sound when i turned it on the next day. So i tried the same thing and it didnt work. I then disabled and reanabled it. It once again worked but only for one day. Ive been doing that everyday and so far it has worked until now. Ive tried everything i can think of but nothing will work anymore can someone tell me whats wrong???

The driver is:
VIA AC'97 Audio Controller (WDM) 5.1.2535.0