for some reason after I turn on my pc, the red light on my optical mouse stay lit up. there are also times when I shut down and the mouse turns off, but then I will come back later and see that it is back on. does this mean there is still power in my pc even after I turned it off? its a usb mouse, that I also hooked up ps2 just to test it, and it still does this. I've never seen this happen before.