Try a different adapter. That MayFlash didn't work on my two 3-button's, and only only a select amount of my 6-button controllers (maybe a little over half of them).

@Furluge yeah i was the reason that raphael learned about the issue which affected a crap ton of controllers. Then he so awesomely found the bug in linux and created the fix for it. But yeah its been fixed for a long ole time. 😊

@Febbweiss

Hi , Anyway I can contact you in a private message or email

You seem to have got something working that I was having an issue with , hope your able to help me

Thank you

I've been fighting this same problem today. I have a bunch of different RetroLink controllers (Atari 2600, NES, N64, Genesis) and they all overwrite each other. My workaround was what @meleu said. I had to hardcode the mappings for each specific retroarch.cfg file and then I configured the NES controller through ES. The fact that you can hot-swap controllers makes it not too bad. I just use the NES controller to navigate and once I fire up a ROM, unplug it and plug in the proper controller.

@hansolo77 said in Problem with Genesis/MegaDrive USB adapters (RetroUSB and Mayflash brand):

Would you be against buying a 3rd party controller?

I'm a stickler for the originals I must say. I've had bad luck with pretty much every single after market controller I've ever tried going back even to the 80's. Even had bad luck with 2x 8BitDo's everybody seems to love. Only lately, ~20 years later, am I having problems with the real console controller brands for the first time (and even that's not their fault as they're now antiques, and I'm using them on a computer and not a console).

@edmaul69 said in Problem with Genesis/MegaDrive USB adapters (RetroUSB and Mayflash brand):

the biggest issue is the cables are crap.

I'll deal with re-wiring them if I have to, in like another 20-30 years when the controllers are going for $100+ each because they're so rare ;)

Right now I have working properly: 4x+ NES controllers, 2x SNES, 3x Genesis, 2x PS1, 2x PS2, and a bunch of Xbox 360 wireless controllers....so even though it took me a ton of trial and error I have at least a set for each proper console I emulate so I'm just leaving it at that. It was just a shame that it took so much trial and error to get to this point. I want to have a 2-player set of controllers for each console, and a backup or two so I'll probably pickup another SNES and Genesis controller, but that's about it.

@massaki
I have some questions:

Is this your adapter?: http://www.mayflash.com/Products/UNIVERSAL/PC035.html Can you plug the three controllers and use them simutaneously? What are the names RetroArch show when you start it (those yellow letters at bottom-left)?