Hi @James_Holland1 and @Andreas_Strobl,
Please accept my apologies for the extreme delay, as we’ve worked diligently to reach every ARC user who has reported a port forwarding issue over the last several weeks. There’s no excuse for having tried your patience, and I hope you’ve at least been able to enjoy Roon 2.0 on your home network in the meantime.
Service providers will have implemented a carrier-grade network address translation for your account if you have a 4G router, likely what’s triggering the MultipleNATFound message in diagnostics.
In its current implementation, ARC can’t circumvent carrier-grade NAT. That said, several users in your situation have rather easily bypassed their ISP’s address translation by using one of the unofficial proxy methods listed in our #tinkering section (such as Tailscale or a VPN).
If you’d like to continue to troubleshoot within the realm of port forwarding, it’s certainly possible that your service provider has a pathway for allowing port forwarding or options for changing out routers, IP addresses, etc. free of charge or for little cost. I recommend you pass along the following questions to their service department:
- Have you implemented carrier-grade NAT for my account level?
- Have you fully implemented IPv6, or do you have IPv4 addresses available?
- Can I request a static IPv4 address to support port forwarding?
- Are there any ports you have reserved at the ISP level I should be aware of?