One of the channels is only DV - you don't mention which channel(s) you're having issues with. If you press the settings button once and scroll up to SAP and set that properly, that may be where the DV is coming from. I assume you're not talking about CC, which is also under the first (quick) settings options
Mystery solved. It's not your box, it's our upconversion.
On SD shows the DV is on track 3. When it's upconverted audio 3 is used for center channel, so the DV needs to be shuffled to audio 7+8 (second PID, Dolby Digital 2.0). Today's show was incorrectly upconverted, as was the show on the 7th. The proper people have been informed. Sorry for the confusion and thanks for the feedback.