Real N64 controller with Mayflash MF103 adapter / control stick issues

[Khaine17]

Unsure if I'm doing something incorrectly, but the Analog/Control stick doesn't work? It isn't even registering as a button to be input when I try to "remap" it within RetroArch controls. This works on the Mupen core, but the parallel core (which I need to use on one of my PCs) does not recognize the control stick at all.

Any help would be appreciated!