Turns out it was as you suspected - an assignment. Found the answer after following the specific instructions outlined in this forum post:References

My Educated guess... The Part Volume is assigned to a Control Assign Knob. Fix... delete the Control Assign. OK, but if that's in fact the case...

Well, good news, everybody - I decided to wipe my computer clean and do a clean install of the OS and followed the installation of the Steinberg drive...

I would probably turn rosetta on for Montage Connect too. Unfortunately that was not an option. No selection available to require the MODX Connect...

This is required only if the Yamaha Steinberg USB Driver, the Yamaha Steinberg Thunderbolt Driver or the TOOLS software that includes the driver is in...

Apologies - I am running the latest Steinberg driver (V3.0.5). I am also using the latest MODX CONNECT download (1.1.01). My Big Sur version is up t...