Hey @Greg_Johnson,
Thank you for the detailed information above. I’d like to keep things a bit more simple here, I don’t think it’s necessary to bring Wireshark into the picture. Arc’s framework might be a bit confusing to a technician who isn’t familiar with Roon, so I can see how they might think port forwarding isn’t relevant. However, port forwarding is going to be the only option for setting up Arc.
Basically, if Arc doesn’t auto-connect when UPnP is activated, then setting up a manual port forwarding rule is the way to go. In fact, if you haven’t, I would disable UPnP if it doesn’t connect out of the box, as there can be hiccups if both UPnP and a manual port forwarding rule are both active.
This is a good first step!
You can find the port number you are using in your Roon Core settings> Roon Arc. Roon uses port 55000 by default (and what my settings are set to,) you can put this number for both range increments. You can also pick a different port if you’d like. Feel free to use any available port in the 10,000 to 65,000 range.
I see that you’re also using Xfinity Comcast, please turn off ‘Advanced Security’ as this has been known to cause issues with Arc. Read more here : “Are you online? Please check your internet connection and try again" [Solved Xfinity firewall] - #49 by David_Ohm
Let me know how the above goes 