[altis]

There problem is the electronics has a hard time working out where the centre zero position is. This is 'cos the joystick sensor is built of analogue electronics that can drift with temperature. There appears to be an algorithm that tries to work out what the average input is and assumes that this is the centre zero. Unfortunately, if you lean on the stick for a long time then it gets confused and starts pulling the cursor back the other way. Solution: let go of the stick and eventually it will stop moving. Also, in use, try to avoid leaning on it for too long - especially at the edge of the screen.