Problem with 4 COntroller Ports Gamecube Adapter

[estrichleger]

Hi there,
I have a 3 in Controller Adapter for the PC, the Switch and the WiiU.
Strange thing is that in the COntroller options from Win10 I can see the GC COntroller and it lets me push the correspodening buttons. Here everything works.

When I try the same thing in Dolphin I cannot get it to work. Does someone know a solution to this problem?