Western Digital EX2 NAS causes my Minis to lose connection to Roamio

I'm totally stuck here, every time I add my new WD EX2 to my home network it crashes the TIVO boxes. The network, until the introduction of the NAS was stable. When I add the EX2 its accessible and the PCs continue to have normal internet access. BUT... suddenly the TIVO (minis) lose their connection to the host Roamio box, their network diagnostics don't change and they are still pingable and have internet access, but whatever mechanism is used to stream from the Roamio is hosed. I believe...

Western Digital EX2 NAS causes my Minis to lose connection to Roamio

Western Digital EX2 NAS causes my Minis to lose connection to Roamio