[mythtv-users] how do I stop prebuffing problems with audio

[kanetse@gmail.com]

On Sun, Sep 7, 2008 at 7:25 AM, Erik van Pienbroek <erik at vanpienbroek.nl> wrote:
> Hi,
>
> I'm also encountering these kind of problems.
> OS: Gentoo, Tuner: DVB-C, Video: nVidia Gforce 5200
> XvMC support has been enabled.
> If I play any recording or live tv (non HD-content) the CPU usage stays
> low (25/40%) but the video and sound are all stuttering (thus
> unviewable). If I disable sound in the mythfrontend (NULL output
> device), video playback is perfect. I've tried applying the Pulseaudio
> support patch which is hanging around at
> http://svn.mythtv.org/trac/ticket/5473 but this doesn't solve the
> problem. Even when I'm using the pulseaudio server on an external
> computer.
>

All these symptoms are the same as what I see - low CPU usage,
disabling sound fixes the problem... I have tried playback on many
different types of hardware, and Linux distros and am seeing the same
symptoms in each case, as long as you don't skip forward or backward
everything plays perfectly.  This leads me to point at my source
recordings as the problem.

My recordings appear to be 1080i, 6-channel AC3, although I'm playing
them over regular analog stereo audio.

To Paul, if you are having the same problem as me, then my prediction
is that switching down to 720p won't solve the problem.  Try playing
back the recording in xine,  it should work 100%.

I've seen this problem on:

AMD X2 5000+ (using ATi HD3200 and/or GeForce 7200 with and without XvMC)
Intel Core2Duo E6420 (ATi Radeon X1950 pro)
dual AMD Athlon MP 1900 (using GeForce 5500 using XvMC)

Unfortunately there aren't a lot of firewire options to tweak, so I'm
nt exactly sure how to diagnose this problem.