My share button stopped 'clicking'. When I stripped the controller down I noticed a small copper coloured dimple on the motherboard was depressed instead of proud like the one for the options button. With bluetack I was able to pull it out but each time I tested it with my finger it clicked once and stayed depressed. I don't think there is a permanent solution to this as it's probably metal fatigue or similar so i put a tiny bit of blue tack overy the dimple so the plunger could push that bit further and hopefully pull it out each time. Seems to work as I reassemble the controller. Fingers crossed it holds out a while! I'd love to know if someone else had a different solution.