Tvheadend

I am trying to use hdhomerun (HDHR3-US), tvheadend and xbmc (frodo) to watch clearQAM channels on a wired, gigabit network. tvheadend is running on linux, xbmc on windows 7. When I watch TV using "HDHomeRun Quick TV" on Windows it more or less works fine without any interruption. However, when I use tvheadend+xbmc, there are constant interruptions. I get frequent "Continuity counter errors". This surprises me because hdhomerun_config seems to be telling me I have a good signal, I'm plugged directly into cable, and QuickTV doesn't seem to suffer as a result of these counter errors. When it's really bad I also get "Transport error indicator" warnings. I don't know what these warnings are telling me.

I would appreciate any guidance on how to troubleshoot this. I am at a loss. Log files below. In the example below the video constantly looks "jerky", in a very rithmatic fashion. Other channels don't behave as bad as this, however they will have regular interruptions.

Thanks!

tvheadend log output
xbmc log output
timestamped hdhomerun_config output

tvheadend version:

$ ./tvheadend/build.linux/tvheadend --version
./tvheadend/build.linux/tvheadend: version 3.5.22~g229a8d7

command to generate hdhomerun_config output:

while true; do (echo -n "$(date) "; hdhomerun_config FFFFFFFF get /tuner0/status; sleep 1) | tee -a /tmp/hdhomerun_config.log; done

HDHomeRun firmware version: 20130117