Please Help, No Sound in Bootcamp

This is my second attempt at using bootcamp to run Windows Vista (32x) on my iMac, and I'm having an issue with the sound. In the bottom right hand corner in Vista I can change the volume, as well as with the f10, f11, f12 buttons on the keyboard. I went to Start--> Control Panel--> Hardware and Sound--> Device Manager and under Sound, video and game controllers it says "Cirrus Logic CS4206A (AB 18)" but has a yellow explanation sign next to it. I've tried to update the drivers, and it says they are up to date. Any suggestions?

Did you insert your OS X DVD after Window Vista was installed in order to install drivers? Have you run the Apple Software update from within Vista to download the latest version of Boot Camp?

Yes, and yes.

If you have the volume control listed in your system tray and the F keys work to control sound but yet no sound, then either the driver is not working, or there is some hardware conflict. The exclamation mark ! over the driver means it's not functioning.

Try removing the sound hardware from the hardware tree, reboot Windows Vista, and let it be detected again. Also, how did you try to update the driver for the sound card?

I just did a Google search on your problem. There are lots of hits and suggestions on how to get the sound working with updated Cirrus Logic drivers. You may have to try several before getting one to work.