I have the mx1000 and it did that on my desk.. But ok .. No biggie... This is why it is called Trouble shooting. have you checked your temperature when you are playing at all ? could be heat from your system.
Every now and then with my mouse I will be going in one direction and all of a sudden I will be spinning like crazy. if I am in a gun it will spin, if I am walking I will spin. it also happens in BF1942 but less often, it's the mouse I am certain, again a stray signal from the mousepad or something. It's not a biggy for me, it doesn't happen that often that it causes me serious problems.
would there be any difference between the accurace of plain printer paper and a mousepad? is the diffrence negligable? maybe its a problem with bf2?
no there shouldn't be an issue. The issue when not using a mouspad or subsitute is, the lazer that is used doesn't pick up on the shear surface of the desk .. and if it does, it picks up the grooves with it.