[mythtv-users] UK Freeview Mux A Jerky Playback Other Mux's Fine?

[nospam312]

When I watch QVC (and other channels on this mux) I get very jerky or
stop start playback but other channels are generally fine.  The
problems are particularly obviously when a horizontal scrolling
message is on screen.  It can be really smooth for a few seconds and
then it jerks and judders for a few seconds and repeats.  If I switch
to BBC News 24 with their horizontal scrolling message it is 99%
smooth.

Can someone suggest what I can do to diagnose the problem and report it.

TIA