MainStage - MIDI program change filtering for external MIDI instrument

When I change patches on my master MIDI keyboard, it's passing the midi program change messages along to MainStage (which is what I want), but it's also sending them to those hardware MIDI instruments controlled by MainStage, which overrides the MIDI program change settings in MainStage channel strip MIDI Output settings. I would like to continue to allow MIDI program change messages to pass from my controller to MainStage (to change MainStage patches), but not to my MIDI hardware instruments, as I still want MIDI program changes stored in my concert patch's channel strip's MIDI Output settings to flow to my MIDI hardware.

How can I accomplish this?