about your specific computer such as make and model and how much RAM it has? Amount of RAM has a very direct effect on running virtual machines (hint, 2 GB doesn't go far) and other components can be stressed also.
I'm running Windows XP Mode through Windows Virtual Machine, with IE9 and Win Exp 7 Pro. I'm using a music recording software called Protools LE 6.4, and I'm running it through a hardware called Mbox (original). I can get Protools running, but there's a lot of interference going on. The interference is worse when I drag the mouse across the screen. It is there even before I crank up the virtual machine.
I've isolated the speakers and also the cable and it's not coming from either. It's definitely associated with the Mbox.
Any ideas as to what might be causing the problem?