Thanks for the Feedback, @Frenchie !
I have a detailed diagram of my setup, but I don’t think I can post it here …
Basically my MIDI control uses a Novation LaunchPad Mini Mk3 (“LMM3”) and (optionally) a FaderFox EC4. I have the CQ mixer app running on an iPad, but for live work, I try to everything with taps on the LMM3. A BomeBox translates LMM3 taps into whatever MIDI is needed by the target systems (Synths, mixers, etc).
I was hoping to be able to control the [Listen] functions and output Hph level by “direct MIDI” to the CQ20B, but not dice. I’m guessing there’s a way with the gnarly Mackie Control protocol, but that’s wayy more complex …