If you are playing a game like Pac-Man™ or Donkey Kong™ and find that the joystick gets stuck when changing directions, this is because these original arcade games used 4-way restricted joysticks, while the X-Arcade™ is set to 8-way mode by default. You can solve this with the X-Arcade™ by changing it to 4-way mode. Note that newer versions of MAME seem to have a built-in software 4-way emulation automatically used for 4-way games (more info see 8).
NOTE: If you are using a newer version of MAME or playing a console version of a 4-way arcade game, you likely do not need a dedicated 4-way joystick. This is because they have a software emulated 4-way mode that tries to interpret diagonals as the next direction instead of getting stuck. This may not be perfect, so you can simply avoid diagonals when you play.
First open the X-Arcade:
The X-Arcade™ was made to be user serviceable, just like a real arcade. It does not void the Lifetime Warranty to open it.
How to change the X-Arcade™ from 8-way to 4-way mode:
To change the X-Arcade from 8-way to 4-way, first open the X-Arcade™ from the bottom to reveal the bottom side of the joysticks as noted above. First you will want to remove the silver "C" shaped metal piece (C-Clip) on the bottom of the joystick handle. Be sure there is something holding the handle side of the stick in from the other side as removing the C-Clip will release it. Using a flat-head screwdriver, put the tip in one of the 2 slots of the C-Clip and pry it sideways away from the joystick handle to remove it (careful, they like to run away from you!). The next piece under that is the 4/8-way Selector, simply remove it and flip it over to change to 4-way mode. (When the fat part of the 4/8-way Selector is touching the microswitches it is in 8 way mode, the thin part touching the microswitches is 4 way mode.) Now replace the C-Clip, and the bottom panel, and enjoy some Pac-Man™!
If your joystick is not hitting a direction, you may need to adjust the microswitches.