New Volumio user here. First, congratulations for your great work.
I have just installed Volumio and I am testing a MOTU M4 audio interface. This one.
It works, although I am playing Lossless content from an iPhone using AirPlay and the Volumio UI reports email@example.com KHz.
Is that to be expected? The interface supports up to 24bit@192 KHz.
Also, are there plans to select outputs? This particular interface is a USB class compliant audio device with 4 outputs and 4 inputs (although in this case the inputs are irrelevant).
I can also report that a Raspberry 4 powered by an Apple USB-C charger can power both the Rpi and the audio interface without issues it seems.