[shillelagh]

I've got one of those and mine started doing that. A mate of mine said are you using a mouse mat and i said yes he said is it a picture one and i said yes and he said chuck your mouse mat and use a one with no picture on it or just use the desk. The sensors dont like having different patterns to bounce off. Tried that and it worked for about 5 mins and started again. Failing that i swapped it over from the one with the 8 pin holes in and stuck it in my usb ports.