Vista - webcam causes conflict with sound

I have a logitech quickcam stx. Before it was working alright but sometimes the mic wouldn't work very well in Skype but unplugging and replugging would solve this.

The real problem came when i reformatted (due to computer running really slow) and reinstalled the quickcam. When plugged into the back usb, it causes the sound (realtek) to stop working. But what is strange is when I plug it into the usb on the front of the computer, everything works fine. Is there an explanation? I suppose it is some sort of resource conflict but I don't know how to fix this.

Also (while being plugged into the back usb) when I uninstall and reinstall the webcam, everything works. But upon restarting the computer, I'm back to the same problem.

I downloaded and installed the latest realtek drivers posted in the "sticky threads". This seems to have solved my problems.