I didn't make it!
While in my quest to get CoD4 multiplayer to work on my Vista PC, I read that the crash error that comes up after you try to get in the game is a sound driver error. So I stumbled across a solution and that is to disable you front panel jack detection. My dilema is that I cannot find where/how to disable it for the life of me. The person that suggested this fix said that the option to disable it was "in the top rightish corner" of the sound manager. This fix is supposedly for vista but the person that said this did not say what version of realtek he had. My version is 188.8.131.5233. Any help is appreciated.
Try entering the task manager and closing the process "RTHDCPL.exe". I have a wobbly connection, and it will constantly detect, then lose, then detect a device again - effectively minimizing anything I've got running every couple of minutes. Plug in what you need, configure it in the control panel, and then close the process.
Not the best solution, but it worked for me.
I'm not aware that there's a process associated with it, but if there is, it will probably keep popping back up unless you solve it via the front panel connections.
If you don't mind going without the front jack detection feature, you may be able to solve it with the following.
On the MB there's a front panel audio header. There are pins on it associated with jack activity detection, usually labeled RET for Return. Try pulling out the wires plugged into those pins. They are the ones for jack detection.