TP-Link Archer C8 there is an additional step to get multicast working (similar to that for the Billion Bipac)
In WAN Settings, below the PPPOE username and password select "Static IP" as "Secondary Connection" type, then input 169.254.1.23 and 255.255.255.0 as IP address and subnet . Reboot and should be good to go. I assume any number in the 169.x.x.x range will do, that is just the example TP-Link support gave.
I'm guessing this solution will apply to other TP-Link routers, eg C9
Many thanks to the People of this forum, ive purchased a new router today as the Current PLUSNET one ive got is being muntered to oblivion by 2 bt homehub 5 wireless connections.... ive managed to get my TV working via my new router thanks to this post ive found in your Help Sections!
Pity the dude on the phone was bloody clueless on the whole subject, but hey ho!... All Fixed now! ... Woo Hoo!!!
Moderator's note by Mike (Mav): Quote fixed.