Showstopper 2000 sometimes loses its serial control over Hughes DSS receiver

There are times when my Showstopper 2000 loses its ability to control direct channel access to a Hughes D45 IRD. You select a new channel on the guide and press Select, but the IRD channel doesn't change (although the Showstopper thinks it has).


The cure is to press the Channel Up or Channel Down buttons (which always seem to work). This seems to re-initialize the serial link. After doing this, channel changes work again.


This is not a sample defect: I have two Showstoppers and two Hughes D45s, and they both behave identically.


I have not been able to determine whether this affects programmed recordings, or only live channel changes.