Re: the xbox controller, it might just be a case of the default deadzone being set to 0%. The analogue sticks do tend to sit a couple of degree off-centre on occasion, which would cause you to drift slightly sideways.
I first encountered this when I purchased my controller for trackmania. Tracks with those stupid push-forward starts (the one's where you shut your eyes and press forward while your car goes on a miniatue rollercoaster ride before the real track begins) proved to be a real nightmare, as veering slightly off course would be fatal.
However over time I guess I've learnt to automatically correct the stick so that it is dead centre before every race, so now I don't even notice it. I'd advise sticking with it, but if it is really bad then you could try raising the deadzone a little.
I first encountered this when I purchased my controller for trackmania. Tracks with those stupid push-forward starts (the one's where you shut your eyes and press forward while your car goes on a miniatue rollercoaster ride before the real track begins) proved to be a real nightmare, as veering slightly off course would be fatal.
However over time I guess I've learnt to automatically correct the stick so that it is dead centre before every race, so now I don't even notice it. I'd advise sticking with it, but if it is really bad then you could try raising the deadzone a little.