[mythtv-users] choppy audio/video in dark scenes

[Zach]

Hi,

I have a problem where the audio (and video?) get's real
choppy/stuttery.   This consistently happens when the scene is
particularly dark such as a black screen with light text.  It happens
in live TV as well as recorder shows.  An example of this are the
promos the Cartoon Network runs just before returning from commercial
break during The Family Guy.  Some commercials also have dark screens
with white or light text.  Some shows which are very dark, such as
X-Files do it to a lesser degree.  This mostly dark screen consistenly
causes the playback to become very choppy.  The audio is the most
noticeable, but it could be the video, too.  It's hard to tell since
it's usually during a still scene.  Does anyone know what may be
causing this and if there is a fix? This is a really strange anomaly;
intuitively it seems that a simple dark background with text would be
less intensive than fast moving video.

 My system originally had 512mb ram, and I added 512mb more to see if
that would help.  I also read something about setting the recording
profiles to 720*480, so I did that (they were 480*480 by default) and
that helped some but not completely.  Plus 720*480 takes up a lot of
disk space, so I'd like to change that back if possible.

The cpu usage is consistenly low (<10%?).

Any help is appreciated.  Will post logs or configs if necessary.

My system is based on KnoppMyth R5A12 (Myth 0.17)
Combined FE/BE
It is a chaintech 7NIF2, Athlon XP 2600+
1GB Ram
Onboard geforce video w/tvout
PVR 250 (debug=1 for ivtv)
Maxtor DiamondMax 10+ (dma enabled)

Thanks
Zach