Gamepad works in RetroArch menus, but apparently isn't recognised at all in games.

So, I was setting up RetroArch to play some SNES games and went into the Input settings to map all the keys to my gamepad (I’m using a Buffalo Classic USB Gamepad, the ones that look like European SNES/Super Famicom gamepads), which made it work in the menus immediately (it didn’t work before I did the whole remapping thing, so it must have done something), but when I try to play a game with it, it refuses to work. As in, pressing any buttons on the gamepad does nothing.

I went back into the menu and realised it shows “(N/A)” after the button values, which… probably means something. Here’s a screenshot to show what I mean. I’m pretty sure it’s not the gamepad, since I tested it with OpenEmu on my Mac earlier, and that worked fine. It also works in the menus, as mentioned before.