Two things that keep me from leaving my QC plugged into my speakers when I’m just using my computer is my desire to not waste electricity, and to turn off the display/button LEDs when I’m not using it as an instrument signal processor/interface.
My idea is you’d press the QC’s power button, and an option that would display is ‘interface mode’ which turns off the display, LEDs, and sleeps other processing so that one can use purely as a USB audio interface.