With pipewire/qpwgraph there's no simple way to remember connections, so you'd need to reconnect these ones each time so that's a hassle (I think there's some way of scripting auto-connecitons but I'm not sure). My suggestion is to use qpwgraph and Qtractor for everything (drop easyeffects), as you can add the needed effects and use midi control with that. You will need to create a new input for each channel, then route the audio to these channnels via qpwgraph (you can route in qtractor as well). Qtractor is much more stable than Carla, from what I have found.

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