Well I use MS Intellimices with an usb connection. i think it's one of the best mices ever produced. However the cable on those babys can be a bit sensetive as I have had one go bad on me + that I heard of others to. This can cause all kinds of odd behaviour, in my case the pointer started flicker like crazy and wonuldn't let me copy/paste properly nomore.. :shrug:

So as mentioned above try it on another computer to see if it's that cable that's causing ya headache.. :)