[mythtv-users] Suddenly, HD-PVR recordings drift out of sync

Jim Stichnoth stichnot at gmail.com
Sat Nov 21 17:59:04 UTC 2009


Starting this past Tuesday (Nov. 17), my HD-PVR recordings have begun
to have audio/video sync problems.  The synchronization starts fine,
but then the audio starts lagging over time.  For example, 30 minutes
into a recording the audio is lagging about 2 seconds behind the
video.  If I stop the recording and restart it 30 minutes in, the
audio is still 2-3 seconds behind.  The same behavior happens if I
copy the mpg file to a Windows machine and view it with vlc.  Older
HD-PVR recordings play back just fine.  I tried reloading the firmware
(latest version 1.0.5.6) but the behavior is unchanged.  I tried
setting the input source (Dish VIP211, outputting 720p) to output pure
PCM or pure AC3, but the lag is there in both cases.

It's almost like video is being set as 60fps but the audio is
59.94fps.  In fact, I ran "mplayer -vo null -ao null -frames 10
-identify filename.mpg" on an old working recording and a new
problematic recording.  For the old recording, the output includes the
line "FPS seems to be: 59.940060", but the corresponding output for
the new recording is "FPS seems to be: 60.000000".

I haven't changed anything in my setup, as far as I know.  I suppose
it's possible that Dish has sent a firmware update.  Any advice on how
to fix this?

Jim


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