AirPlay not working in macOS Tahoe

ChatGPT and I have spent hours trying to fix this problem. Here is GPT's conclusion after I did a lot of testing:

macOS 26 + Music AirPlay Bug (Summary)

What happens

• AirPlay devices (HomePods, AVR, Sonos) appear in Music and can be checked, but audio is silent.
• Mid-track dropouts.
• Master Volume stops working (global slider has no effect).
• Only reliable fix in-session: uncheck all AirPlay devices, then re-check (toggling just one doesn’t work).

What’s not the problem

• Devices are online and reachable.
• Network config is fine (same setup works on iOS and on a fresh macOS 26 install).
• Static IPs don’t solve it (issue persists even with pinned addresses).
• Configure IPv6 setting from Off to Link-Local Only had no effect
• There is no VPN on this system

What’s really happening

• Logs show AirPlayXPCHelper probing non-existent IPs (e.g., 192.168.50.x, 192.168.4.x) and timing out.
• Sometimes it “self-heals” after long idle; other times it stays stuck until forced to rebind.

Workarounds

• Toggle all AirPlay devices off/on inside Music.
• When Master Volume is dead or audio is silent, killing and restarting the coreaudiod and AirPlayXPCHelperprocesses restores functionality.

Conclusion

This is a macOS 26 AirPlay stack bug: AirPlayXPCHelper caches bad addresses and gets stuck in a “connected but silent / master volume unresponsive” state. Apple needs to fix the helper’s discovery/cache logic and session state handling.