MAME Tab Menus Not Responding

Hello, everyone.

I have MAME32 .84u2, Windows 7 Pro 64-bit.

I tried running it this morning, and under the Tab menu, I'm unable to set the joypad to customize commands for the games, nor does the keyboard respond. I simply can't select anything on the menu. The "5" works for credit input, but I cannot select characters or move.

Previously, I was able to use both the keyboard and the joypad to set up games without problems. This was last year, and nothing has changed in my PC since then. I have joypad input and mouse input both selected.

I have recently changed control pads after my Saitek broke, switching to a Sabrent 12-button. I have tested the controller on VirtuaNES, and it operates with no problem.

Thank you in advance for any help with this issue.