Bug Xbox 360 button issues

Some of my players are having issues: the buttons on their xbox 360 controllers are not registering inputs (see thread: https://steamcommunity.com/app/2198030/discussions/0/3787002916511577295/) and I have no idea what could be causing it. However the joystick works. Could anyone point me in a direction?

Here's the code I use to access input, it's really simple (segment is an integer between 0 and 3):

Code (CSharp):

1. Gamepad pad;
2. Keyboard key;
3.  
4. _GetController(controllerId, out pad, out key);
5.  
6. switch(segment) {
7.   case 0: return (pad != null && pad.buttonEast.wasPressedThisFrame);
8.   case 1: return (pad != null && pad.buttonSouth.wasPressedThisFrame);
9.   case 2: return (pad != null && pad.buttonWest.wasPressedThisFrame);
10.   case 3: return (pad != null && pad.buttonNorth.wasPressedThisFrame);
11. }

Thanks