DVR not recording certain channels anymore?

We have the original Contour setup (not Contour 2) and have been VERY pleased with our DVR. We set recording times for shows we like; and there's no trouble.

Lately...quite a few channels won't let us record, pause, fast-forward...nothing. Channels that we know have this problem are:

Smithsonian Channel

Can anyone explain why this is so? We've done all the "usual fixes" that the phone tech's recommend...nothing.

Ideas, thoughts??