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My VLC (v2.0.6) is showing numerous different errors like these

main audio output warning: PTS is out of range [...] dropping

and

main audio output warning: computed PTS is out of range [...] clearing out

These errors result in an audio glitch. What does PTS stand for? How do I resolve this error?

Here is part of my log,

[0x7fcef4000978] main audio output warning: computed PTS is out of range (121844), clearing out
[0x7fcef4000978] main audio output warning: PTS is out of range (121844), dropping buffer
[0x7fcef4000978] main audio output warning: computed PTS is out of range (122275), clearing out
[0x7fcef4000978] main audio output warning: PTS is out of range (102275), dropping buffer
[0x7fcef4000978] main audio output warning: computed PTS is out of range (122650), clearing out
[0x7fcef4000978] main audio output warning: PTS is out of range (82650), dropping buffer
[0x7fcef4000978] main audio output warning: computed PTS is out of range (123016), clearing out
[0x7fcef4000978] main audio output warning: PTS is out of range (63016), dropping buffer
[0x7fcef4000978] main audio output warning: computed PTS is out of range (123408), clearing out
[0x7fcef4000978] main audio output warning: PTS is out of range (43408), dropping buffer
[0x7fcef4000978] main audio output warning: computed PTS is out of range (124218), clearing out
[0x7fcef4000978] main audio output warning: PTS is out of range (24218), dropping buffer
[0x7fcef4000978] main audio output warning: computed PTS is out of range (125181), clearing out
[0x7fcef4000978] main audio output warning: PTS is out of range (5181), dropping buffer
[0x7fcef4000978] main audio output warning: computed PTS is out of range (126122), clearing out
[0x7fcef4000978] main audio output warning: PTS is out of range (-13878), dropping buffer
[0x7fcef4000978] main audio output warning: computed PTS is out of range (126720), clearing out
[0x7fcef4000978] main audio output warning: PTS is out of range (-33280), dropping buffer
[0x7fcef4000978] main audio output warning: computed PTS is out of range (127091), clearing out
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Which OS and audio driver? I'm guessing a Linux distro and alsa... –  Dennis Feb 13 '13 at 19:40
    
Linux and Pulse. –  Evan Carroll Feb 13 '13 at 19:51
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1 Answer

See the VideoLan bug tracker -- the second result on google for this error message.

You are probably playing a video file with a PES stream (Packetized Elementary Stream). Due to the design limitations of these data, they can't be properly synchronized. So when your video plays at an irregular rate , or when the streams aren't kept in sync by dedicated hardware, the software notices (when it's too late) that they're out of sync, and drops frames in the audio buffer to fix it.

Almost all graphics drivers produce some latency or jitter in the framerate, and even then the piezoelectric quartz crystal driving display timing doesn't match up perfectly with the audio timing crystal, so if the software doesn't have data to keep the audio and video in sync from the data in the video file, you get problems like this.

Note that there is very expensive hardware that may be able to keep the streams in sync at a hardware timing level, but usually these systems are for production crews in studios.

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but, I'm playing an oggopus stream -- you can play it yourself if you'd like radio.evancarroll.com:8000/stream.opus –  Evan Carroll Feb 13 '13 at 22:33
    
I didn't know we still had crystals in use in modern computers... tsk tsk –  Jay Apr 1 '13 at 5:06
2  
Uhm, they are. If you downvoted my answer for talking about quartz crystals in modern PCs, read the answers in the linked question. Get a clue -- there's no reliable way to handle event timing without an extremely regular (periodic) timing mechanism, and quartz crystals do exactly that. –  ÃŁŁǫǛȉЖΦΤїҪ Apr 1 '13 at 13:46
    
@Jay - so what is then used, instead of quartz crystals, for timing in PCs? –  sdaau May 26 '13 at 15:41
    
I had a similar problem playing some videos on VLC with some bad playing , video did not play smoothly. Smplayer played smoothly the same video. –  Aftershock Jul 4 '13 at 15:13
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