Portcls.sys Windows 7 BSOD URGENT

Hi there, I have recently been encountering more and more frequent BSOD due to "portcls.sys" this has stumped since I have a practically no name dodgy sound card which I cant even find a model number on so cannot find any driver updates etc etc. I managed to find the download page of the company "C-media technologies" however when trying to download anything I have to login to some random page in chinese. Not going to happen. I am running windows 7 64 bit premium, an intel x58 MSI motherboard, 6.00 GB ram and as i stated a "C-media PCI audio device" of which I do not even have a model number for etc or can not find any information about.

This is really starting to bug me as the BSOD are happening at the most inconvenient of times. I have attached a Crash report . If anyone could possibly link me to a fix or updated drivers ANYTHING as this is starting to do my head in. Much appreciated
thankyou

Welcome to W7 Forums.

We need the crash dump files in c:\windows\minidump directory.

Do you have Windows Service Pack 1 installed?
Have you run Windows update?

I would like to try and switch over to my onboard sound card however i have no idea how to do this, i have tried plugging my microphone and speakers into the onboard ports howver it is not displaying sound through it, i think it might have been disabled so the current unstable sound card is the only one being used ?, if so how can i switch over to my onboard sound car for my motheboard