HDHR Prime Lost Tuning On One Channel

I thought I'd start here, then move to mythtv-users and then only as a 
horrible last resort try Comcast tech-support.

I lost one of my Comcast channels on my HDHR Prime. Channel 805 H2HD 
*was* recording fine and now records with sort of a broken black field 
and occasional bits of the sound and some noise. This actually happened 
some weeks ago but I wanted to wait until I upgraded to 0.24.3-282 
(which is as far as I can go on CentOS-5 for now) to see if it was some 
kind of codec problem.

Checking the channel from the command line with hdhomerun_config still 
shows the channel subscribed and cci unrestricted:

$ hdhomerun_config 1310D399 set /tuner2/vchannel 805
$ hdhomerun_config 1310D399 get /tuner2/vstatus
vch=805 name=H2 HD auth=subscribed cci=unrestricted cgms=n/a

Does anyone have any thoughts?

Thanks,
Kirk Bocek