The fire cube is on the same network as is the server. It will connect remotely, but not directly.
I have several wifi connection points in the home and three DVR servers (I experiment with them). I also have a vpn on tge firecube and that turned out to be tge issue! Even though I had it turned off the cube was trying to route tge connection through the vpn.
I deleted the vpn and it was able to connect. So I reinstalled the vpn and excluded the channels DVR app. That worked too. All along it was probably a vpn issue.
The channels app had never before exhibited an issue with the vpn and it’s been on the cube for over a year. Maybe you’ve recently changed something in either the client app or the server app that caused the issue. Or maybe tge vpn app had an issue. In any case, the elimination of vpn solved tge problem
Dan Lewis