Mainstage NO SOUND OUTPUT, but controller is recognized

I had a fully operational Mainstage all the up through soundcheck. Once showtime hit though, I'm no longer getting any output signal from Mainstage.

The Mainstage software recognizes the midi controller (see photo with red circle), but not getting any output (see photo with red circle- output meter doesn't register any sound). All my previous mappings function without an issue, and as far as I can see, nothing is being muted in the mixer.

I switched over to other software- both Logic and Garage Band operate without any issues. I've deleted and reinstalled Mainstage (which cost me $35 because I had an older version of MS), still same issue.

Under the MIDI tab in Settings, it says "2 MIDI inputs detected". I'm getting nowhere resolving this issue.

I appreciate any help. Thank you in advance.