If you are happy with what you have now, I agree that you could just keep using the optical connection. My preference is to use a network connection with UPnP, all controlled from the Naim app, but if you have a setup that suits you, there’s nothing wrong with sticking to it.
Having said that, the two servers you mention are very well supported by their developers, and a few knowledgeable people on this forum can probably help too if you decide to keep trying.
ChrisSU:
I would really like the functional capabilities of the app, so I will keep trying to figure out the UPnP connection. I’ll definitely come back for more assistance.
For now, I wanna listen!
Thanks again, Everyone!
@daniel I use Audirvana Plus on an iMac to stream UPnP to a Mu-so. It works well even at 24/192. My iMac has a 5 GHz Wi-Fi connection to an Airport Extreme (802.11ac). The Mu-so has its Ethernet wired. This suits me because I mostly stream from Qobuz. If you have your Hi-Res content on your Mac, you can run MinimServer on the Mac and control the Mu-so using the Naim app.
david
I’ve found Minimserver to be good, but those who have compared generally seem to say that Asset is easier to set up and use, so that would be my suggestion.
Good luck.
I would post your current network setup as something here maybe the cause of you issues. Are you running any software firewalls that might be blocking UPnP traffic?.
I connect to a WiFi network, but I would like to have a wired connection. My iMac and Mu-so are only 5 feet from each other.
The Firewall was active until now. I’ll give it another try.
FINALLY GOT IT!!! Audirvana+ is working now. I’m not sure why, but it works!
Thanks Everyone!
Daniel
I had it for about an hour, then the built-in speakers took over. Mu-so Qb not recognized and naim app unable to detect it. I’m absolutely perplexed!
Thus, I have learned that it is possible to have a UPnP connection with Mac and Mu-so Qb. I’m just frustrated. My happy face balloon deflated. 
Now, to begin another day. I’m so lost. Another day.
Try the trial version of Asset UPnP. If you can hard wire everything via a switch better still. Easy.
Cdboy
What do you mean… hardwire via switch?
Thanks
Daniel
Be thankful, I think optical out has gone completely from later iMacs…
+1
Mac via ethernet (CAT5e will do) to a switch via ethernet to the Mu-so. Create a little local network. If you have a router run that into the same switch. Your Mac may need an USB/ethernet adaptor.
I would suggest thats not a great solution.
Have you tried another lead, its starting to sound like a dodgy lead there.
I tried Audivarna last night to see for myself and it seems a bit flakey with the new Naims. Would not see my Naim Atom over UPnP at all and several other endpoints that are UPnP capable also did not show. All other software I have used works fine with UPnP discovery , Naims app, Roon etc, BubbleUpnp, Asset, MinimServer,. So it seems it’s does not like something that every other software is happy with.
Perhaps I’ve misunderstood what you’re doing, but do you mean that the Server input on your Atom can’t see the server?
Either Naim does not see Audivarna library as UPnP server ( not sure its supposed to) and Audivarna does not see the Atom under its list of endpoints. The only one that does show up is one pi that is running running a upnp renderer upmpdcli. This is odd as it’s also running on another pi that does show up , or some wireless speakers that are also UPnP compliant.
I’m aware that Audirvana does now have a UPnP server, that works on OSX, and I think Windows 10. If it’s like any UPnP server I’ve used, once set up, you don’t need to enable any UPnP streamer or even look for it in the server. You just search for the server on the streamer, and if everything is working properly, it should be there.
It all setup just doesn’t work for me no idea why and dont have the inclination to try, AudiVarna allows you to push to the endpoints as its acts as a control point and server combine but the Uniti doesn’t show up nor does the server in Naim app as UPnP server. TBH I dont care as i use Roon, just wanted to see if it could be used for Qobuz and if it would be Gapless. But I cant try either so experiment over.
I have found that Audirvana+ sometimes looses the UPnP link to Naim streamers and it is not shown in the Preferred Audio Device list. A restart of the app or the streamer usually brings the connection live again.