I have a new CCR 2004 router installed and service clients through PPPOE on radius. However clients are reporting about TV streams like netflix, prime, apple tv not to be working on their TVs.
Also updates are not working it keeps on showing an error of network unreachable. But IPs and DNS is fine and all these clients have internet on phones and laptops. TVs fail to stream they show an error but youtube works on the TVs meaning it gets internet.
Those symptoms could be linked to a MTU problem, which is likely if PPP encapsulation is used. And exacerbated when firewalls block ICMP too much.
The easiest way to confirm that may be by lowering the MTU of a client interface where downloads are made. On the client machine, and to like 1400 or under. If that’s an instant fix for downloads then that’s your issue.
As for the fix it will depend where it’s reduced bellow 1500 in your setup. I don’t understand where PPPoE is used here, on the ISP side or to connect clients. There are options to deal with that at the PPP level if you’re the server. Or you’ll have to do “TCP MSS clamping” using a mangle rule on the firewall, for traffic going out to the PPPoE upstream interface. Very common config you can search about on the forum or the web.