I have a bunch of endpoints in my house. Whenever there is an update (Mac OS or Roon) all but one of the endpoints stop working until I deal with the computer that’s running Roon. Without fail I only notice this at an inconvenient time when I’m trying to listen on one of my other endpoints.
It didn’t use to be like this. Really annoying.
Well, I don’t think you’re alone. Sounds like Mac updates have this impact on a lot of folks. Sorry to hear it.
If you want to take a trip to ROCK/MOCK-land, there’s a pretty cheap path there:
This is a MAC issue, roon rock is the way to go and will end the need for maintenance.
I would review options such as the one suggested above.
I’ve had similar issues every time since Apple released MacOS Sequoia. But after dropping my MacBook Pro as a server in favor of first a Linux powered Lenovo laptop and later a NUC such as Johnny_Ooooops has listed, Roon behaves as it should. 
Apple has really borked up MacOS with the Sequoia release. After every OS update I had to reboot the MacBook Pro as endpoints were gone again.