Two of my controllers have been playing up lately, its best described as drift - if you are moving around and sometimes you will continue to walk / move in a direction when you 'stop' or take your thumb off the stick. this is (obviously) without touching the thumbstick. i hadn't realised that this has been happening for several months (and just been feeling really bad about my play style - but it is now noticeable to the extent that i know it isnt me!

in both cases its the left thumbstick - which seems to be the exception (as always :p):
- on the halo 4 (console version) controller - the person keeps going to the right (the stick never feels stiff or is out of alignment - that i can see).
- on my halo reach controller the left thumbstick keeps moving forward, again its not always and it doesn't feel stiff or out of alignment.

anyone any suggestions to fix this? ideas? for something 'minor-ish' replacing both seems extreme.

Not sure if this will work for the 360 controller, but when I had this issue (or something similar) with a PS2 controller, rotating the analog sticks around a few times in each direction would temporarily fix it

Welcome to gaming experience.
Maybe this will help you:
http://www.overclock.net/t/1259816/how-to-fix-xbox-360-controller-stick-drift

Had the problem so many times myself....its real annoying

If you're on a computer you can usually adjust the deadzones but if you're on console, well...

Broke far too many lockpicks in FO3 because of that issue.

From my experience, that is a hint it's on it's way out. However that might not be the case. I would open it up and make sure the insides aren't bent/broken.

Get a nine inch nail and nail the stick into place. No more drifting.

On a more serious note, if you feel comfortable with the idea you can take the controller apart and try re-seating the stick if you think it is getting worn, so it might work for a while longer. Yet when you are getting this behavior they tend to be on their way out.

Images of what little is inside a controller. http://www.pcbtrain.co.uk/blog/printed-circuit/video-game-controllers-dismantled/
EDIT :: I was in such a rush to put in my little joke that I did not see that darthspudius had already given the same answer.

Thanks, really appreciate it +rep too, ive ordered a security torx (its the only type i dont have ><) to open them up and have a look. fingers crossed.

i can understand how the Reach one is getting old (yet its not as bad as the H4 one) - you do not want to know how many assassinations that made me mess up! Tthe H4 one hasnt had much use and its been doing it for ages, should have sent it back really.

will update if i find anything, hoping i might get away with something that doesnt require soldering as iv not done it before since school! and do not have any equipment!

Have ordered some new ABXY buttons too just for fun, some [url=http://www.ebay.co.uk/itm/170705121260?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649]chrome[/url] ones and some silver [url=http://www.ebay.co.uk/itm/281040818348?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649]bullet [/url]ones - didnt get the dpad ones as i think it will spoil the look. Plush BRITISH made and these guys are the original makers too! so worst case i get to mod the controller even if it doesnt fix it :). Think they will look awesome in the controllers.

edit

Well, "usually". You have to resort to third-party software because Microsoft, most other hardware manufacturers and most game developers are idiots (because it takes a friggin' mastermind to insert "if x > abs(deadzone)" into the script that handles the controller input). Fixing the dead zone in case of the Xbox 360 wireless controller is still a pain in the ass, not even completely sure it works perfectly by now. The tools I tried which allowed setting a deadzone for this controller turned it into a Direct Input device which is ass when playing newer games.