Well it was worth a try (4.9.3).
You can check the LOG in TuneBrowser, it may give a clue to why you are having a problem?
Use the TB main menu and navigate to:
VIEW -> DOCKING WINDOW -> LOG VIEW
The LOG will appear at the bottom of the screen … have a look in the UPnP tab.
On my system (see screen show) you can see the time the network … and the point where the
If that does not help, I will have to defer to other TuneBrowser experts…
P.S also check your PC Firewall/software setup, perhaps there is a (default) block in place?