I'm helping a friend convert his SF II cab to run Mame. Using a JPAC to do keyboard encoding. All works well, except that button 3 on the player two side sends a lower case Q...but Mame won't recognize it.  In Notepad, it's clearly being sent properly.  But when I hit TAB and go into program the controls, it won't accept the q character at all, either from the button or from the keyboard. It will let me assign pretty much any other key...but not q.  What am I missing?
On a related note, I have another Mame cabinet that's working fine and has been running for a long time.  It only has 2 player buttons but it randomly sends the lowercase q character.  Not sure where it's coming from yet.  Mostly it's harmless and just causes a beep since it's not assigned to anything. But if I'm in Notepad editing something it will insert the letter q in random places as I'm typing.  Strange
Thoughts?