I bought a 6 button controller to use with my RetroPi setup, and it is recognised and configured easily. At least it seems so.
Unfortunately, once I start up a game (say Sonic) no button does anything. I try hitting every button, but no response at all. The only thing that does anything is using my keyboard to enter the meny or quit the game.
Once I am back in the meny of Emulation Station the controller works again. Up/down/Left/Right/A/Start/Select: it all works. But not in the game.
Clues on how to start debugging wtf is going on?