I have a macbook pro which i just updated with macOS Sierra. My Sonos was completely fine and all of a sudden it was unable to access my music library, saved on the macbook in the default iTunes folder. I tried re-adding the default music folder to the Sonos music library, only to get a message saying 'Sonos was unable to add the music folder. The computer "....." cannot be found'. I tried adding the location manually through the second option in the music library settings, and got the same message again. I read a few threads recommending changing firewall settings and restarting the router, but no solution. Any advice?