No problem! I was a bit tired writing this.
I got a Behringer X Air 18 digital mixer. This mixer can act as a 18x18 audio interface. This allows me to send/receive audio to/from the host system. This is freely routable. In my use-case this means:
The XR18 has 4 internal effects which can be used as (stereo) send-effects. But the routing can be overwritten to a different destination. So instead of sending the signal from a channel to the internal effect, I want to send it to the Mod Duo X via USB. There I want to process it and return it to the XR18. So on the Mod Duo X I need to reconfigure some stuff (At least ALSA and Jack I guess) to use 8 channels of the XR18 as the input source as well as the return path.
In my performance I want to send channel 8 to a EQ; distortion, compressor, channel 9 to a EQ, compressor, gated reverb, EQ; channel 1,2,5 and 6 to a delay + reverb; the mixer sum to a reverb.
And yes, I’m aware of the limited resources of the Mod Duo X and maybe 8 channels are too much with multiple reverb etc.
Has anyone tried USB audio routing part so far?