I have multiple Apple TVs (bedroom, kitchen, patio, shop etc that I feed systems in those rooms via the optical out of the Apple TVs. Roon doesn’t really like Apple TVs or airplay that much it seems. I get major dropouts and pauses in Roon when I try to do zones via airplay plus you can’t zone Airplay and regular together so it doesn’t work for me. I wonder if there is a model of roon endpoint that could replace my apple Tvs?
I think you could use a Raspberry Pi with a audio HAT of your choice (that provides the needed outputs of course) and run RoPieee or any other suitable OS distribution on it to solve the task.
And Apple TV will only do CD quality, nothing more. I stopped using my Apple TV 4K except for Apple Music and Netflix.
I know I want something that is a roon endpoint can accept ethernet and has optical out but is an official Roon end point so I won’t be dealing with the inconsistencies of trying to use airplay and roon endpoints together. That doesn’t work at all and I found that out after buying Roon and Nucleus etc… I often like to have my main system playing and many by bedroom and kitchen all at once. I can’t do that now with Roon
As @BlackJack said a good option is to go for a Raspi with a HAT - you said you want ethernet connectivity and optical out so you could for example use Hifiberry Digi+, a JustBoom Digi HAT or Audiophonics Digipi+ PRO – if you want a readily built solution by a Roon partner maybe the Baby Ambre will do.
A Bluesound Node would work well for this?
Maybe or maybe not:
I happend to have a bluesound node 2i laying around so I tried it and it works. I haven’t played with it long enough to experience dropouts. I have had major dropouts when playing to airplay devices via roon and you can’t mix airplay with a regular endpoint which was my whole idea to get a roon endpoint, they say it works so much better. I have to say the Node did seem to sound immediately better than the apple TV I was using via optical to my Kef LS50W in my kitchen