Airplay destinations not visible on macOS 12.2 iMac

I have approximately 9 Apples devices at home (3 macs, 3 iPads, 3 iPhones) and they they ALL can "see" all of the legitimate AirPlay destination devices EXCEPT for one iMac. That single iMac, (Intel i9, running 12.2 if it matters) can only see a SUBSET of the AirPlay destinations that I have at home.

I have two M1 Macminis, one on 12.2 and one on 11.6.3, and they both can "see" all AirPlay destination devices.

By "see" I mean that an AirPlay destination device is listed as expected in the Sound tab within Mac System Preferences", or the equivalent in the iOS/iPadOS Control Center.

Any idea what could be wrong?