[mythtv-users] Audio problem with HD using XvMC

[Patrick Ouellette]

On Thu, May 03, 2007 at 10:18:29PM -0400, Siva Alagarsamy wrote:
> 
> Hi,
> When I use XvMC with HD channels, the audio break up often and I see lot of
> these messages like these.
> 
> 
> 2007-05-03 15:31: 18.312 WriteAudio: buffer underrun
> 2007-05-03 15:31:18.298 NVP: Video is 7.24978 frames behind audio (too
> slow), skipping A/V wait.
> 
> 
> I have AMD Athlon64 3000+ processor with 512MB RAM,  ATI HDTV Wonder, NVIDIA
> FX 5200 video card & SB Live card
> I have ubuntu feisty(i386) with the latest kernel and mythtv packages.
> 
> Without XvMC, I have no problem with the video or audio. I trying to get
> this XvMC working, so I can setup another computer for frontend with a less
> CPU power.
> 
> I have XVideoTextureSyncToVBlank & XVideoBlitterSyncToVBlank turned off in
> nvidia settings.
> The xorg.conf has "UseEvents" set to "true". I have tried different NVAGP
> options.
> 
> XvMC works fine with mplayer. I tried playing a HD recording with mplayer
> -vo xvmc and it plays without any problem. If I watch the same recording
> with MythTV, I get audio stutter problem with lot of "WriteAudio: buffer
> underrun".
> 

Have you enabled extra audio buffering?  That clears up the stuttering
on my system when running XvMC.

My system: AMD64 3000+, 512MB RAM, NVIDIA 6600, NFORCE 4 chipset using
S/PDIF out (ALSA drivers), on Debian SID.

Pat

-- 

Patrick Ouellette                 pat at flying-gecko.net
kb8pym at arrl.net                   Amateur Radio: KB8PYM 
Living life to a Jimmy Buffett soundtrack
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