Unable to add previously known AirPlay device to Home App.

Yamaha RXA Airplay2 receiver no longer shows in Apple Home App.

Until recently the device showed up in Home app under the relevant room, but it’s now no longer visible and therefore not accessible via Siri. 

Attempts to re-add the device via:

+ Add Accessory > More Options” functionality - Results in error message…“unable to add accessory. Make sure your iPhone is connected to WiFi and try again”. With a second, overlaid error dialogue message… “AirPlay. Unable to connect to Yamaha”.

Noteworthy: 

a) the Yamaha is visible, connectable and functions via AirPlay from either Apple Music App or Control Center on multiple Apple devices.

b) I did successfully add another previously unknown AirPlay speaker to Home app via same method without any problem.

c) Created a new Home on a different Apple device with a different Apple ID - received exact same Error message.

• Rebooted iPhone / Yamaha / Router.
• Reset Network settings on Yamaha / iPhone.
• Erased and renamed Yamaha network ID.
• Disabled all other HomePod HomeHubs except one.
• All devices are on latest software/firmware versions.

Have read reports of folks with Sonos and Denon equipment having experienced same issue after iOS 16 architecture upgrade, resorting to factory resetting their devices with some limited success. However, as the Yamaha has been visible in Home app until recent, this seems weird, unless an iOS17 update introduced another bug.

Any ideas appreciated.