mDNS/Bonjour issue on RBE971 running firmware V12.1.11.15_5.4.12

Additional troubleshooting findings — both network connectivity and Control Center behavior

I wanted to provide an update following further testing.

We've now isolated two different failure conditions:

1. Network connectivity failure: On one occasion, the original Key Light became completely unreachable from my Mac on the main SSID (100% ping loss and HTTP timeout). Switching only the Mac to the IoT SSID immediately restored connectivity and control, without rebooting or resetting either light.
2. Control Center failure despite successful network communication: At other times, both lights are discoverable through macOS Bonjour, and I can physically turn the original light on and off using direct HTTP commands from Terminal. Both also work in the iPhone Elgato application, yet the Mac Control Center application fails to recognize or control the original light.

I've since reinstalled Control Center, cleared its local settings and caches, and verified Local Network permissions. The problem persists.

Two additional details:

• The issue began about seven weeks ago on a previous Mac Studio and continues on a new Mac Studio configured from scratch. The original Key Light worked reliably for years; the newer light was purchased only after the problems began.
• An earlier extended Bonjour monitoring log showed frequent device removals, but further investigation revealed that many coincided with macOS sleep/wake events. Those entries should not be considered independent evidence of router multicast failures.

I'm now investigating this with Elgato support as well.

I'm not certain whether these represent separate issues or an interaction between Orbi's wireless-client communication and Elgato's discovery software.

I'd particularly appreciate NETGEAR engineering's input on why switching the Mac from the main SSID to the IoT SSID can immediately restore IP connectivity to a device that otherwise becomes unreachable.