Hi Pete,
Here is a link to a thread about what I think you are talking about. Have a read through it and it will explain what is happnening!
http://community.wd.com/t5/WD-TV-Live-Streaming/TMDB-not-working/m-p/737990#M30836
I Assume that this is also affecting the WDTV Live Hub which is the device you are talking about.
Ayhan