pi@max2play ~ $ cat /opt/max2play/audioplayer.conf
### Configuration of Audioplayers
SQUEEZELITE_PARAMETER=-o plug:plugequal -a 80:::
SQUEEZESLAVE_PARAMETER=-n plugequal
SHAIRPORT_PARAMETER=-d default:CARD=ALSA
USE_USB_DAC=0
USE_EQUALIZER=0
You know… I remember, that I have clicked once this button: „Reset configs to Max2Play delivery configuration“
Maybe this cleared it? I thought on fresh system it won’t do any damage.