Still getting "Last content source has been removed"

I’ve had the WD TV for a few months. I had this problem at the beginning and discussed it here, but I can’t find that now. I’m running an iMac and Playback media server. The WD TV will usually run for a couple of minutes, then post, “the last content source has been removed”. Somehow I got that fixed the first time, but in the last week the problem has appeared again.

I’ve reset the WD TV and even restored the original settings, to no avail. I’ve used other media server software, also to no avail. This is some kind of problem with the WD TV, and I would really like it to go away… before the WD TV does.

Any ideas?

Thanks!