I’m not sure I understand the question. Why would an antivirus program like Norton have an audio output to a Sonos speaker? 

I think the firewall is blocking interaction with the apps on mobiles. If I have Norton installed it will not pick up the app for about 30 seconds when you open it up on a mobile? It’s a common issue, I found out about it through ***SONOS*** support this is how I knew to remove it. 

My question is how do I configure the firewall so I can still have Sonos and NORTON!

Since I have removed Norton from my PC on the network I have had no connection issues with mobiles. Surely there is a way to configure Norton to allow SONOS activity?

You can’t believe the difference without Norton. Norton blocks everything,

If I install Norton back onto this windows PC now, tomorrow when I wake up speakers will not be available on the network and the app will not work for about 30 seconds upon opening it...

If the FAQ from Sonos doesn’t help, I’d be contacting the folks at Norton…after making sure I’ve updated their definitions. 

Funnily enough, it will work from the machine that the Norton is installed on though.