Game version: X3TC (Steam) version 3.4 2017
Controller: PS4 Wireless
Playing through Steam with PS4 support enabled. (Steam emulates it as an Xbox360 controller and the game detects it as such. That's normal behavior)
I was able to replicate this bug in 2-ways:
1st Way:
2nd Way: Save game while docked at any station. Exit game and launch it again. Load save. D-pad broken. (Inconsistent)
Here is how I fixed it (temporarily):
- (in-game) Settings > Controller
- re-bind each individual controller action, including the sticks and save the changes.
Mine were always set to default so I literally just had to re-assign them to default again. Even if the binding itself didn't visually change in the settings, it somehow fixed the bug.
NOTE: This fix only works until the next time you load a save file and undocking breaks it again. Then you have to repeat the process.
NOTE #2: When rebinding the controller actions, make sure you don't rebind the B button first, as that will somehow prevent all controller bindings from functioning except the B button. If you messed up and changed B first, you will have to use a mouse & keyboard to finish rebinding the controller actions.