Best guess for where to post this:
Two M1 Macs, both on latest Monterey (MBP and Mini). Both run local Music libraries and stream via airplay to multiple appletv's (4k and newer) and homepod mini speakers.
The mini generally works reliably - every couple of months I have to reboot the network and mini when it starts acting up, but not often enough that I notice.
The M1 MBP though is a different story. It'll work all day, but then the next day I get 'Cannot connect to this airplay device for music playback' (paraphrasing text). Sometimes it's just on one appletv, but often it won't airplay to any device. The only thing that works is a reboot of the machine, then it'll work the rest of the day, but next morning it fails again. The mac doesn't sleep overnight.
I've tried cycling wifi, killing and restarting mdnsresponder, even deleting and re-creating the wifi connector, but it never works again until I reboot the machine.
Clearly something in the network stack (I suspect related to bonjour) is failing after a few hours. I've tried removing little snitch, but that has no effect. I've tried with IPv6 on, local-link, and automatic, which makes no difference. When the MBP fails, the mini, iphones, and ipads still works to the same target appletv, so I'm 99.9% sure the issue is with something on the laptop, but I'll be damned if I can figure out what it is.
Apple stuff (airplay, automatic airpod switching, etc) works until it doesn't, and then it's a major pita to trouble shoot because it's a total black box. I know if I call into apple they'll tell me to wipe and reinstall the OS to see if that fixes it (they did that for a preference problem on another machine recently), but that's a non-starter.
Anyone out there figured out where in the network stack the airplay/bonjour subsystem sits? I'm perfectly happy to simply kill and restart the process to fix this, if I knew what it was.
<<<< Ain’t this junk app>>>> 
