This happens every day, sometimes more than once, and its happening on both of my WDTV Live Streaming units.
I was using regular shared folders and the Content Source Not Found would show up, so I setup the Media Server on the NAS and it works great, except after being idle for a period of time, I come back and it tells me the source isn’t found. I go back to the Main Screen and go back into files and everything shows up just fine. Why is it continually losing its source?