Chosen Solution
So, I have a Xbox One S controller with a stuck B button. I called Microsoft and they are sending me a new one and letting me keep the old one. So, I was wondering if I could fix the messed up button. It registers as pressed constantly but is not physically stuck. Has been tested on 2 Xbox Ones and a PC.
You can try this teardown below and see is something is possibly jamming the B button under the rubber as shown in step 8. It might be a software issue as well, but it’s worth a shot to take it apart if it’s not working anyways. Xbox One Wireless Controller Teardown
Rubbing alcohol on a q tip wipe around edge of button and press the button rapidly no more sticky button your welcome
