It would appear that my X52 is dying. The YAW is now permanently moving left a little, locking the stick doesn't help, so have to apply constant left YAW to conter it, not to great, and now the pinky/shift button has broken.
Bah. Hum. Bug.
Time to buy some torx screwdrivers and strip the stick. Sneaky of them putting the torx in there, 3 normal screws plus torx in the hand guard/hight doodaa.
Don't suppose anyone has had to fiddle with the stick innards before?
Very common issue, electrical contact cleaner sprayed into the potentiometer which is in the base of the handle. Worth a try before you have to buy a new stick.