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.
NOTE: If you are using a newer version of MAME or playing a console version of a 4-way arcade game, you do not need a dedicated 4-way joystick. This is because they have a software emulated 4-way mode that simply interprets diagonals as the next direction instead of getting stuck.
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™!