I can't get buttons remapped

I know this is an old subject, but my second hand PiCade doesn’t seem to want to let me remap the buttons. When I go into the onscreen config input menu, it always goes to “keyboard” no matter what button I press on the controller panel or device sides, whether or not I have a keyboard plugged in.

This is one of the older units with the swinging door on the back.

Any thoughts?

I guess I should also say that I can’t get the unit to return to the menu once a game is selected. Pressing what I think are start and select together doesn’t work here. That is the reason I want to be able top assign buttons to functions. Any help on that problem?

I figured out how to call up retroarch and get back to the menu by selecting “quit”, so it’s all good.