I was watching last night's Premiership Rugby on BT Sport 1HD when the picture started to break up really badly. I flicked to 2HD which was the same but strangely 3HD was fine. All the non-HD BT Sport channels were also fine so I gave up and watched in SD. Twenty minutes later I tried again and 1HD was working fine again.
A speed test showed 32 Mb/s download and 11 Mb/s upload. I connect to the hub via a high speed TP Link powerline.
Any ideas why some HD internet channels would work fine but others didn't?
I checked my Netflix - whcih is connected to the same TP Link and that also was working fine.