Strange sub-channel issue w/Dish dvr
 

I have a strange issue with a local pbs sub channel and a Dish Hopper w/sling dvr. The situation is as follows...........

PBS channel 68-1 & 68-2 are received fine by all TV's & dvr's. Channel 68-3 plays fine on all of the TV's, but not on the dvr's. There are times that the picture tunes in, but no sound. I have deleted the channel & rescanned several times, but no luck. I have talked to the channel engineer & he states that there is noting different in the settings for this particular sub channel versus the others. I would think using common sense, that something is slightly different in the 3rd sub channel.

Anyone have any ideas?