Recently I’ve been noticing that my HP Pavilion desktop running Windows 7 Ultimate doesn’t automatically enter standby mode anymore. It used to but sure doesn’t lately. I could manually do it but not automatically. I thought perhaps it was a tab in a browser causing the issue but it would have the problem if I just boot the computer and didn’t open anything (except what the computer boots with). I finally decided to try to figure out how to solve the problem.
I came across a nice post from Lifehacker entitled How to Find Out What’s Keeping Your Computer from Going to Sleep. It said to go to Start -> Programs -> Accessories, then right-click on Command Prompt to open it as administrator then type “powercfg -requests” to see what’s keeping the computer awake. In my case, it was “IDT High Definition Audio CODEC”. Try as I might, I couldn’t figure out how to solve the problem. I read many web pages. I went to HP’s site and downloaded the latest driver. I used msconfig to see if the problem would go away if I turned services and startup items off.
Using msconfig and a whole lot of trial and error, I figured out that turning off Multimedia Class Scheduler would solve the problem. Unfortunately, I found out that Windows Audio needs Multimedia Class Scheduler when I tried to manually turn it off in services so that wasn’t a practical solution. (I did turn off several other non-Microsoft things that I didn’t know were launching behind my back though).
In the end, the best solution was the simplest, and something I read in a couple of web pages but initially ignored. Opening device manager, I saw IDT High Definition Audio CODEC under Sound, video and game controllers. I deleted the IDT High Definition Audio CODEC entry. It asked if I wanted to delete the driver and I said yes. I then rebooted and Windows automatically discovered it and put it back with a default driver. As the French say, Voila! It worked.
The moral of the story is try the simple things first. How hard is it to delete it and have Windows automatically put it back?