[mythtv] Strange issues with MPEG channels on QAM

Joshua M Thompson funaho at jurai.org
Sun Feb 11 06:51:48 UTC 2007

I've got an HDHomeRun connected to Comcast (QAM-256), which I use to
record both my local ATSC stations and some of my favorite basic cable
channels. The problem is that on the non-ATSC channels the front end
seems to barf on occasion, resulting in black screens, a black & grey
screen with audio (left 1/3 or so is solid gray, right 2/3 solid black),
randomly morphing program lengths (an hour program might show up as 0:55
or 1:08), and seemingly random commercial skipping.

The problem areas seem to occur where Comcast has inserted local
advertisements in the stream. When they occur Myth seems to lose sync
with the stream. When this happens the front end spits out thousands of
lines like this:

[mpeg2video @ 0x108ba24]get_buffer() failed (stride changed)

Sometimes it recovers, sometimes it aborts back to the recording screen,
and on occasion it just crashes.

Has anyone else seen this? I checked Google and Trac and couldn't find
any other mention of this. I'm running SVN 12770 but this has been
happening ever since I started recording these channels many many SVN
revisions ago.

Joshua M Thompson <funaho at jurai.org>

More information about the mythtv-dev mailing list