Just started getting playback issues with freezes/jitters. Happen on both SD and HD programs and usually in the same place in the recordings. However waiting a while and playing back the recording corrects most of the issues. Since LINHES.org was down, i tried lots of things unsuccessfully. Running R8.1 on two HDHomeruns with and old Nvidia card.

2014-06-28T14:42:31.762234-05:00 mythtvquad frontend: 2014-06-28 14:42:31.754398 N Resuming idle timer
2014-06-28T14:42:48.986499-05:00 mythtvquad frontend: 2014-06-28 14:42:48.915977 I TV: Creating TV object
2014-06-28T14:42:48.992265-05:00 mythtvquad frontend: 2014-06-28 14:42:48.943178 N Suspending idle timer
2014-06-28T14:42:49.016522-05:00 mythtvquad frontend: 2014-06-28 14:42:48.944490 I TV: Created TvPlayWindow.
2014-06-28T14:42:49.016680-05:00 mythtvquad frontend: 2014-06-28 14:42:48.947050 I TV: Attempting to change from None to WatchingPreRecorded
2014-06-28T14:42:49.219669-05:00 mythtvquad frontend: 2014-06-28 14:42:49.151344 N AudioPlayer: Enabling Audio
2014-06-28T14:42:49.320109-05:00 mythtvquad frontend: 2014-06-28 14:42:49.230017 I AFD: codec AC3 has 6 channels
2014-06-28T14:42:49.320381-05:00 mythtvquad frontend: 2014-06-28 14:42:49.230747 I AFD: Opened codec 0x10b44560, id(AC3) type(Audio)
2014-06-28T14:42:49.320658-05:00 mythtvquad frontend: 2014-06-28 14:42:49.230828 I AFD: codec AC3 has 2 channels
2014-06-28T14:42:49.320913-05:00 mythtvquad frontend: 2014-06-28 14:42:49.231242 I AFD: Opened codec 0xae50f60, id(AC3) type(Audio)
2014-06-28T14:42:49.321183-05:00 mythtvquad frontend: 2014-06-28 14:42:49.232369 I AFD: Opened codec 0x39dd460, id(MPEG2VIDEO) type(Video)
2014-06-28T14:42:49.321439-05:00 mythtvquad frontend: 2014-06-28 14:42:49.233060 I AOBase: Opening audio device 'hdmi:CARD=NVidia,DEV=1' ch 2(6) sr 48000 sf signed 16 bit reenc 0
2014-06-28T14:42:49.421816-05:00 mythtvquad frontend: 2014-06-28 14:42:49.404052 E ALSA: no playback control PCM found on mixer device default
2014-06-28T14:42:49.422277-05:00 mythtvquad frontend: 2014-06-28 14:42:49.404062 E ALSA: Unable to open audio mixer. Volume control disabled
2014-06-28T14:42:49.684512-05:00 mythtvquad frontend: GetModeLine - scrn: 0 clock: 148500
2014-06-28T14:42:49.684589-05:00 mythtvquad frontend: GetModeLine - hdsp: 1920 hbeg: 2008 hend: 2052 httl: 2200
2014-06-28T14:42:49.684606-05:00 mythtvquad frontend: vdsp: 1080 vbeg: 1084 vend: 1089 vttl: 1125 flags: 5
2014-06-28T14:42:49.722922-05:00 mythtvquad frontend: 2014-06-28 14:42:49.686204 I Setup Interrupt handler
2014-06-28T14:42:49.723397-05:00 mythtvquad frontend: 2014-06-28 14:42:49.686216 I Setup Terminated handler
2014-06-28T14:42:49.724929-05:00 mythtvquad frontend: 2014-06-28 14:42:49.686335 I VideoOutputXv: XVideo Adaptor Name: 'NV17 Video Texture'
2014-06-28T14:42:49.815457-05:00 mythtvquad frontend: GetModeLine - scrn: 0 clock: 148500
2014-06-28T14:42:49.817161-05:00 mythtvquad frontend: GetModeLine - hdsp: 1920 hbeg: 2008 hend: 2052 httl: 2200
2014-06-28T14:42:49.817167-05:00 mythtvquad frontend: vdsp: 1080 vbeg: 1084 vend: 1089 vttl: 1125 flags: 5
2014-06-28T14:42:49.818445-05:00 mythtvquad frontend: GetModeLine - scrn: 0 clock: 148500
2014-06-28T14:42:49.818465-05:00 mythtvquad frontend: GetModeLine - hdsp: 1920 hbeg: 2008 hend: 2052 httl: 2200
2014-06-28T14:42:49.818470-05:00 mythtvquad frontend: vdsp: 1080 vbeg: 1084 vend: 1089 vttl: 1125 flags: 5
2014-06-28T14:42:49.824681-05:00 mythtvquad frontend: 2014-06-28 14:42:49.783501 I OSD: Base theme size: 1280x720
2014-06-28T14:42:49.824698-05:00 mythtvquad frontend: 2014-06-28 14:42:49.783523 I OSD: Scaling factors: 1.5x1.47222
2014-06-28T14:42:49.825103-05:00 mythtvquad frontend: 2014-06-28 14:42:49.814414 I OSD: Base theme size: 1280x720
2014-06-28T14:42:49.825111-05:00 mythtvquad frontend: 2014-06-28 14:42:49.814433 I OSD: Scaling factors: 1.5x1.47222
2014-06-28T14:42:49.825401-05:00 mythtvquad frontend: 2014-06-28 14:42:49.818593 I Player(5): Video timing method: USleep with busy wait
2014-06-28T14:42:49.825524-05:00 mythtvquad frontend: 2014-06-28 14:42:49.818867 I TV: Created player.
2014-06-28T14:42:49.825644-05:00 mythtvquad frontend: 2014-06-28 14:42:49.818920 I TV: Changing from None to WatchingPreRecorded
2014-06-28T14:42:49.825864-05:00 mythtvquad frontend: 2014-06-28 14:42:49.820352 I TV: Main UI disa bled.
2014-06-28T14:42:49.825984-05:00 mythtvquad frontend: 2014-06-28 14:42:49.820406 I TV: Entering main playback loop.
2014-06-28T14:42:50.026856-05:00 mythtvquad frontend: 2014-06-28 14:42:49.987518 I VideoOutput: Created YV12 OSD.
2014-06-28T14:42:58.135126-05:00 mythtvquad frontend: 2014-06-28 14:42:58.047444 N Player(5): Waited 102ms for video buffers AAAAAAAAAAAAAAAAAAAAUUUUUUUUULLP
2014-06-28T14:42:58.635956-05:00 mythtvquad frontend: 2014-06-28 14:42:58.603766 N Player(5): Waited 102ms for video buffers UUALLAAAAAAAAAAAAAAAAAAUAAUUUUUP
2014-06-28T14:43:02.439294-05:00 mythtvquad frontend: 2014-06-28 14:43:02.402768 N Player(5): Waited 102ms for video buffers AAUAUAAuUALUUALUAAAAAAAAAAAAAAAP
2014-06-28T14:43:04.141043-05:00 mythtvquad frontend: 2014-06-28 14:43:04.092058 N Player(5): Waited 102ms for video buffers AAAUAULALUAAAAAAAAAAAAAAUAAAUUAP
2014-06-28T14:43:04.441512-05:00 mythtvquad frontend: 2014-06-28 14:43:04.420405 N Player(5): Waited 102ms for video buffers AAUUUUuALUAAAAALAAAAAAAAUAAAAAAP
2014-06-28T14:43:04.742052-05:00 mythtvquad frontend: 2014-06-28 14:43:04.670710 N Player(5): Waited 102ms for video buffers UUAAAAAAALAAAAAAUAUAUAAAUAUALUUP
2014-06-28T14:43:04.942526-05:00 mythtvquad frontend: 2014-06-28 14:43:04.869946 N Player(5): Waited 102ms for video buffers AAAAAAAAAAAAAUUAAUAUAUULAuLUAAAP
2014-06-28T14:43:05.042935-05:00 mythtvquad frontend: 2014-06-28 14:43:04.971959 N Player(5): Waited 204ms for video buffers uLAAAAAAAAAAAAAALAAAUAAAUAAAAUUP
2014-06-28T14:43:05.243483-05:00 mythtvquad frontend: 2014-06-28 14:43:05.193873 N Player(5): Waited 102ms for video buffers AAAAAAAAAAAAAUUAAULUAULUAUUUAAAP
2014-06-28T14:43:07.345655-05:00 mythtvquad frontend: 2014-06-28 14:43:07.274879 N Player(5): Waited 102ms for video buffers AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAP
2014-06-28T14:43:07.445925-05:00 mythtvquad frontend: 2014-06-28 14:43:07.377209 N Player(5): Waited 205ms for video buffers AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAP
2014-06-28T14:43:07.546269-05:00 mythtvquad frontend: 2014-06-28 14:43:07.479872 N Player(5): Waited 307ms for video buffers AAAAAAAAAAAAAAUAAAAUAAAUAALAAALP
2014-06-28T14:43:09.948569-05:00 mythtvquad frontend: 2014-06-28 14:43:09.862236 N Player(5): Waited 103ms for video buffers AAAAAAAAAAAAAAAAAAAAAAAAAAAAAALP
2014-06-28T14:43:13.852134-05:00 mythtvquad frontend: 2014-06-28 14:43:13.804570 E decoding error
2014-06-28T14:43:13.852157-05:00 mythtvquad frontend: #011#011#011eno: Unknown error 541478725 (541478725)
2014-06-28T14:43:14.453001-05:00 mythtvquad frontend: 2014-06-28 14:43:14.364543 E decoding error
2014-06-28T14:43:14.453024-05:00 mythtvquad frontend: #011#011#011eno: Unknown error 541478725 (541478725)
2014-06-28T14:43:14.453296-05:00 mythtvquad frontend: 2014-06-28 14:43:14.404745 E decoding error
2014-06-28T14:43:14.453305-05:00 mythtvquad frontend: #011#011#011eno: Unknown error 541478725 (541478725)
2014-06-28T14:43:14.453562-05:00 mythtvquad frontend: 2014-06-28 14:43:14.443887 E decoding error
2014-06-28T14:43:14.453571-05:00 mythtvquad frontend: #011#011#011eno: Unknown error 541478725 (541478725)
2014-06-28T14:43:14.554048-05:00 mythtvquad frontend: 2014-06-28 14:43:14.483039 E decoding error
2014-06-28T14:43:14.554071-05:00 mythtvquad frontend: #011#011#011eno: Unknown error 541478725 (541478725)
2014-06-28T14:43:14.554343-05:00 mythtvquad frontend: 2014-06-28 14:43:14.523232 E decoding error
2014-06-28T14:43:14.554352-05:00 mythtvquad frontend: #011#011#011eno: Unknown error 541478725 (541478725)
2014-06-28T14:43:14.654849-05:00 mythtvquad frontend: 2014-06-28 14:43:14.562376 E decoding error
2014-06-28T14:43:14.654877-05:00 mythtvquad frontend: #011#011#011eno: Unknown error 541478725 (541478725)
2014-06-28T14:43:14.655069-05:00 mythtvquad frontend: 2014-06-28 14:43:14.601515 E decoding error
2014-06-28T14:43:14.655075-05:00 mythtvquad frontend: #011#011#011eno: Unknown error 541478725 (541478725)
2014-06-28T14:43:14.655241-05:00 mythtvquad frontend: 2014-06-28 14:43:14.607631 I OSD: Base theme size: 1280x720
2014-06-28T14:43:14.655429-05:00 mythtvquad frontend: 2014-06-28 14:43:14.607652 I OSD: Scaling factors: 1.5x1.47222
2014-06-28T14:43:14.756375-05:00 mythtvquad frontend: 2014-06-28 14:43:14.706556 E decoding error
2014-06-28T14:43:14.756404-05:00 mythtvquad frontend: #011#011#011eno: Unknown error 541478725 (541478725)
2014-06-28T14:43:14.856845-05:00 mythtvquad frontend: 2014-06-28 14:43:14.762825 E decoding error
forever...

At this time I am not sure if it hard drive, video or ethernet signal, sound, and/or configuration.

It would appear that you a have a problem with ALSA sound. It's not finding the correct device for sound.

Try this



What does it say for?

Card:
Chip:

Card: HDA NVida
Chip: Nvidia GPU 14 HDMI/DP
Item: S/PDIF

Noticed this on a recording that was ending and then switched quickly to live tv and the playback jitters where also on live tv for that channnel as well. Signal lock was 96 and 100 on the HDHomeRun tuning on a cable HD local broadcast channel. It was not happening on other cable local broadcast channels at the time.

Also note that 3 to 4 shows where recording at the time on 2 HDHomeruns (Cable & OTA) only this channnel had issues. Note that the jitter is not on the same channel and or frequency.

Checked the channels on HDHomeRun PC tools:

Signal Strength %: 100%
Signal Quality %: 88% - 92%
Symbol Quality %: 100%

During video playback there were not real spikes in the signals or audio jitters. However there were video artifacts in the signal every 40 seconds or so. So looks like some type of signal issue and decoding.

There seems to be a bug in mythtv in around this on a combination backend/frontend system while recording and playing non hd content at the same time.

http://www.gossamer-threads.com/lists/mythtv/dev/563847

I replaced the amplifier on the cable signal and the problem went away for a while, but then came back, but not as often.

Thinking that this still was a hardware issue, I dug more into Nivida settings. If found a reference for the the following option at http://www.mythtv.org/wiki/VDPAU#Tearing.2FStuttering



After adding this to the /etc/X11/xorg.conf.d file I have not had anything more than a random stutter every week or so.

My video card is a GeForce GT430 which is speced to handle all VDAPU modes.

My theory is once the system would hit the triggering condition, everything would stacks up, causing mass stuttering. I did notice that the stuttering would go away when a commercial was playing sometimes(HD or SD). Guessing that re encoding of content from the tv station and/or the cable provider of the non native HD content was stressing the video card.