I pack my controller up in my backpack and lug it around with me. Lately, when playing games, the screen and/or mouse will drift around. This is controlled by the right thumbstick which seemed stiff and recentered itself well enough. I decided to unscrew the front from the controller and have a look. I then unscrewed the board from the back, used some compressed air on the thumbstick and what do you know – all fixed. Saved myself $20.