Major mouse lag

Never seen this before, but my brother just used my PC to play CF.

My mouse is working fine out of game, but as soon as he started the game and joined a match it wouldn't move right.

He could move any other way but not right.

It then goes back to normal, 10 minutes later in another game it does the same thing.

He tried playing COD, and that was normal. So I assume it's CF?

Help me please

*Mouse is just a regular desktop mouse with a wire and a red light underneath (I don't know what they are called)