Network Conflict?

I have a network with a number of wired and wireless connections. With the WD Cloud device connected, one of my computers loses network access and its internet connectivity is reduced to a crawl. Shut the WD Cloud down and everything returns to normal. No other devices are affected, all can see the NAS and each other. Router is a Virgin Media Super Hub with DHCP so all devices have unique IPs. No port forwarding is configured. I’m stumped.

Anybody got any ideas?

I guess you could try assigning the WD a static address outside of the DHCP range to make sure there’s no conflict. Otherwise you could configure your router to reserve an address for the WD. You would need the MAC address for that.