Hi,
Are the adapters in wall sockets, not in extension blocks ?
Have you tried swapping the adapters round ?
Also, try manually setting the network connection on the YouView box, in the Settings Menu go to Network & Internet, toggle to Manual and then use the following:
IP address 192.168.1.100
Subnet mask 255.255.255.0
Default gateway 192.168.1.1
DNS 8.8.8.8
Thanks
Karl