I've had the same problem, reset bios and everything including re-installing the drivers multiple times.
Also my sound decided to quit working on my ASUS CM5570 after a windows update, I was able to re-install the driver after installing, and uninstalling multiple times for about and hour. It quit again and after hours and hours I give up.
Was thinking of getting another sound card, now I'm thinking of getting another motherboard.
Unless there's some other people have the same issues as Luke_Vader and I.
I'm at a loss also. Any help is GREATLY appreciated!