Every time my computer is idle for a few hours or more, the next time I try to use it, I get an error saying that no audio device is installed. If I restart, everything is fine. What’s happening and how do I fix it?
Thanks!
Install XP 
It’s hard to say without knowing more about the hardware you’re running. Is it onboard sound or is it an add in card like a Sound Blaster? Or is it external? If it’s external, there could be a power management setting shutting it off if it is idle for a set period of time.
Other than that, I couldn’t really guess except to say that audio drivers for Vista are a little lacking right now and it could be a driver issue.
I have heard of this happening with '98 and XP too.
Haven’t a fix for it I’m sorry to say.
I’m also almost embarrased to say that I have a pair of Toshiba laptops running Vista that have never had a single problem.