Same problem here.
Ethernet ports didn't work on installation day. I managed to get them working by plugging in the telephone adapter into the top port on the superhub 3.
5 days later and the ethernet ports all stopped working. Tried factory resets, power off for 30 mins, plugging telephone in and out but nothing.
Wifi working fine.
When the ports died today the Wifi also went off and I also noticed a red wifi and network symbol on the TV box but those disappeared when the Wifi came back.
Going to to keep plugging away (literally!) as I need the wired connection for work tomorrow!