The RAM on one of my laptops is being consumed up to 100% by the svchost.exe which runs the Plug and Play service. I'm running VISTA

The problems/symptoms are:

1. 100% RAM usage
2. Vista doesn't detect new hardware
3. The device manager list is empty
4. When I try to access the properties of plug and play in services.msc it comes up with a Configuration manager error.
5. if I end the svchost.exe process with task manager and restart the plug and play service the problem goes away but after a restart the problem returns

It doesn't fix the problem, but it has revealed a new symptom.

When I go into my Audio devices, there are no audio devices listed. It seems that the sound card is causing the problem. I've tried to reinstall the driver, but it wont because the sound card isn't in the audio devices list. I'm going to guess plug and play is trying to install it or something along those lines. I'm going to give safe mode a shot.

EDIT: Hasn't fixed anything. I've got the sound devices back and turned off enhancements but the problem persists.