Failed to init FMOD system error code 51

For my PC I use a Rodecaster Duo that uses virtual channels for sound. I changed the source of the sound ingame and I shouldn't have done this, cause now I can't play POE2 with sound anymore. When I disable the Rodecaster POE2 runs, but I'm not able to fix the problem. After changing the audio input to the right source, I exit POE2 and start up my Rodecaster again and POE2 gives the same failure message. Somehow I was able to run POE2 before the error message occured, while using the Rodecaster.

I've uninstalled and installed POE2 twice after the error message, but
it didn't solve it.

Too bad that POE2 doesn't have a technical support forum like POE1 does :-(

I use Windows 11 as operating system.