Some days ago my Audirvana Remote App refused to establish contact with my laptop. At first the app at least seems to try to connect, but actually I get the »Can’t-connect«-screen right from the start. See screenshot.
I checked everything I can think of, even reinstalled the app several times, without any success.
Can you check your firewall settings? In Settings > Update and Security > Windows Security > Firewall and Network Protection > Allow an application through firewall, make sure that Audirvana is allowed to access the network.
Restart your WiFi router because it may have a problem transmitting the connection used by Audirvana Remote (Like the Apple Remote app that controls iTunes, which can be blocked for the same reasons)