Hello @Scott_Tweddale,
Glad to hear that you have been able to pinpoint the issue to the Router’s firewall, that’s great news and we’re definitely on the right path towards the solution here!
Can you please post a screenshot of your Router’s firewall page? Generally speaking it’s here that you have to add Roon and RAATServer as an exception for the IP address of your Core. You can usually find the IP address of your Core in the Router’s DHCP list and I would also recommend that you setup you Core as a “Reserved IP Address” so that the Core’s IP address doesn’t change between router reboots and negate the firewall setting you are setting up here.
A list of specific ports that you need to forward can be found here:
And a user has also mentioned these ports (depending on the router/application):
If you are still having troubles after excluding these ports from the firewall, please let me know and I’ll see what else I can do to assist.
Thanks,
Noris