Third Phantom is up to date on the latest firmware. There are no differences between the Phantoms. All have connnected to the WiFi network but the third is not recognized by Roon. I am only connecting one at a time.
An app such as FING can be used to run an IP search to verify if all Devialets have IP addresses. The other method would be by logging into your router (typically this can be reached at 192.168.1.1) but for the router aspect you may want to refer to instructions from the manufacturer.
In case you haven’t done so yet, I would also suggest rebooting the Networking Gear, Devialet and Core (in that order) to see if it helps.
What is the IP address of your MacBook Pro running Roon? All of your devices should be on the same subnet 192.168.1, so I would think there would be a lot of devices with those same first digits.
It may be a pain to do this, but have you tried swapping the non-responding Phantom in the same setup as a responding one? The Phantoms do odd things like switch to Network over powerline, and you don’t really have control over that. Might be good to know if it is the device, per se, or the location.
The Roonbridge endpoint like Danny talked about works very well with Roon. I have ethernet to the Roonbridge and SPDIF out to the Phantom. That allowed me to smash my Dialog to pieces with a sledgehammer (which gave me much joy). It works better than it ever had before. It shows up as the Ropieee device, not the Phantom.
To make it wireless you could probably just put a wireless access point in front of the whole thing.
Thanks for the update. It’s helpful to learn how all these things work, and sometimes don’t work.