Hello, Please help. I allowed someone use my computer last night. Now, I am having issues with it. The issues are probably related. When I move the mouse, every few seconds, the pointer on the screen suddenly stops for a second or two, then can move again. The computer then makes a double sound, like "klunk-klunk." This is extremely annoying and has to stop. The klunk-klunk sound happens sometimes when I'm not even moving the mouse. (Note: It's the same sound that routinely happens when I plug something into the USB port.) Please help me to fix the problem.