Another SVCHOST.exe problem

For the past few weeks, I have been having a problem with one of my svchost.exe processes. It gradually increases it's memory usage by 4kb every couple seconds, eventually taking up alot of memory and making my computer very laggy. I usually just restart to solve the problem, then it's back after a few hours.

I've narrowed the problem to the spcific svchost.exe using Process Explorer.
The command line is:
C:\WINDOWS\system32\svchost -k rpcss, and for anyone that knows anything about the rpcss driver, its very important to the smooth running of your computer. I've tried suspending it and everything becomes inoperable, and of course killing the process gives me the 1 minute shutdown warning.

The one thread in the process properties:
kernal32.dll!CreateThread+0x22

well theres 5 of those actually and 3 of them are what is taking up the resources, fluctuating back and forth between them. Would it be helpful if I posted the Stack information for these threads?

Any help is appreciated. Ive already scanned my system multiple times for any type of spyware/malware...i'm always virus free.

 

Any ideas?