I built a new htpc about 2 months ago and installed Ubuntu 11.10 x86_64. The system records TV with MythTV. I use MythTv and Boxee for playback. After 15 minutes up to 6 hours of video playback, something causes playback to drop to about 1-2 fps. AC3 passthrough audio stutters at the same rate, but pulse audio remains normal. Logging out resets/fixes the issue, but the stuttering will start again after another 15 minute to 6 hours of playback (I haven't noticed a correlation with the varying times). Getting up a few times during a program to log out, log back in, restart the video is getting annoying.
The video card is an Nvidia Geforce GT 520. I've experienced this issue with both VDPAU and software decoding. Connection is HDMI to a 1080p TV. I use the Nvidia HDMI audio.
I tried the ubuntu-x-swat PPA, but there was no change, so those lines are now commented out of my apt sources.
I've been using Ubuntu for about 5 years and am generally pretty savvy, but this one's got me stumped.
(Hopefully) relevant system data:
$ dpkg -l | grep nvidia
ii nvidia-common 1:0.2.35 Find obsolete NVIDIA drivers
ii nvidia-current 290.10-0ubuntu1~oneiric~xup1 NVIDIA binary Xorg driver, kernel module and VDPAU library
ii nvidia-current-updates 280.13-0ubuntu5 NVIDIA binary Xorg driver, kernel module and VDPAU library
ii nvidia-settings 290.10-0ubuntu1~oneiric~xup1 Tool of configuring the NVIDIA graphics driver
ii nvidia-settings-updates 280.13-0ubuntu1 Tool of configuring the NVIDIA graphics driver
$ uname -a
Linux t3 3.0.0-14-generic #23-Ubuntu SMP Mon Nov 21 20:28:43 UTC 2011 x86_64 x86_64 x86_64 GNU/Linux
$ dmesg | grep -i nvidia
[ 65.630897] nvidia: module license 'NVIDIA' taints kernel.
[ 66.195170] input: HDA NVidia HDMI/DP,pcm=3 as /devices/pci0000:00/0000:00:01.0/0000:01:00.1/sound/card1/input5
[ 66.195215] input: HDA NVidia HDMI/DP,pcm=3 as /devices/pci0000:00/0000:00:01.0/0000:01:00.1/sound/card1/input6
[ 66.195328] nvidia 0000:01:00.0: PCI INT A -> GSI 16 (level, low) -> IRQ 16
[ 66.195334] nvidia 0000:01:00.0: setting latency timer to 64
[ 66.195427] NVRM: loading NVIDIA UNIX x86_64 Kernel Module 280.13 Wed Jul 27 16:53:56 PDT 2011
EDIT: (summary of comments) I started logging GPU temperature to see if there was any correlation to the stuttering. I have not found a correlation.
I've also noted that it will sometimes go into 1-2 fps stuttering mode while sitting idle for a few hours; it stutters the next time it is used, and I must log out, log back in to clear it.
* * * * * echo `date`: `nvidia-smi -q | grep -A 1 Temperature | tail -n 1 | awk '{print $3,$4}'` >> /home/tom/gpu.log– Tom Dec 29 '11 at 23:40