[mythtv-users] Stuttering video on mythtv 0.26

HP-mini blm-ubunet at slingshot.co.nz
Thu Nov 22 20:48:15 UTC 2012

On Thu, 2012-11-22 at 17:12 +0800, Ben Kelly wrote:
>         I recently upgraded to mythtv 0.26. Everything works fine,
>         except for
>         some videos which have very bad stuttering. These videos play
>         fine on
>         0.25. I've also checked mplayer, which plays them very
>         smoothly as
>         well. I have an nvidia ION card and I'm using the "vdpau
>         normal"
>         profile, but I've been through the others (OpenGL, etc) and
>         the
>         problem is always the same on myth 0.26.
>         I used the video playback test under the Setup Wizard in the
>         frontend.
>         SD is ok, but the HD test gets stutter. I've noticed that the
>         log gets
>         filled with these on videos experiencing stutter (and this
>         includes
>         the HD test):
>         "CoreContext mythplayer.cpp:2095 (PrebufferEnoughFrames)"
>         I've set the nvidia powermizer to max performance, updated to
>         the 304
>         nvidia driver, turned off CPU scaling - none of which have
>         made any
>         difference.
>         My setup is:
>         - Zotac Mag - Atom 330 CPU
>         - ION nvidia graphics
>         - Mythbuntu 12.04
>         - Mythtv 0.26

Do you have any of the deprecated vdpau filter text items added to your
vdpau video playback profiles.
One of the removed filter options is vdpaustudiolevels, I forget the
others that have been removed.
The filters are available there but are enabled from the GUI OSD menu.

Do you have the dreaded alsa buffer size warning in your logs:
"ALSA: Unable to sufficiently increase ALSA hardware buffer size -
underruns are likely" ?

Not sure how any of these would cause your network bandwidth problems

Can run "mythfrontend -v playback" to increase debugging output. 

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