I only have a x-arcade solo so I don't have a P2 button.
But..I opened notepad.exe and I noticed that my buttons are producing output. For example my left white button located on the side of the x-arcade spits out the number 3. The right button spits out number 4. My white player 1 start button spits out number 1.
The controller works fine in Mame32, but it does not work with mame commandline & mamewah.
Please help, I really want to use Mamewah as a front end.