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pitch/speed changes

Posted: 03 May 2010 21:58
by daWsOn_s
This has probably already been reported or it's not a bug at all since I've been "feeling" this for years but never asked.

During playback all of kind of files I noticed that the playback changes speed and and so the tone, randomly, with speed-ups and speed-downs. It's not an huge change i think it's a +/- %1, but I can hear it clearly.

The only thing that comes to my mind is that the playback could lose the audio/video sync and tries to re-establish it with those speed changes. But this also happens to audio files so I don't see a connection there

Am I missing a simple option to disable? :D

Re: pitch/speed changes

Posted: 04 May 2010 01:02
by Jean-Baptiste Kempf
Is your computer overclocked?
Can you try VLC 1.1.0-pre3 to see if it fixes your issue?

Re: pitch/speed changes

Posted: 04 May 2010 02:04
by daWsOn_s
It's not. I said this has been present for years with different PCs over that time, I've updated the releases constantly. It surprises me nobody ever experienced it.
I'm using the latest nightly build right now (DXVA support) and I'm trying to see if it presents the problem too, I have to use if for a little bit. why did you ask about the latest "pre", is this a known bug resolved in that release?

Re: pitch/speed changes

Posted: 04 May 2010 21:13
by daWsOn_s
Yes the last build has it too

Of course you have to disable time-stretching audio to ear the difference

Re: pitch/speed changes

Posted: 05 May 2010 11:35
by VLC_help
You run AMD setup with cool&quiet enabled?

Re: pitch/speed changes

Posted: 05 May 2010 13:35
by daWsOn_s
I got an Itel machine

Re: pitch/speed changes

Posted: 06 May 2010 12:57
by VLC_help
What does Tools -> Messages... (set Verbosity to 2) complain when the problems happen?

Re: pitch/speed changes

Posted: 06 May 2010 13:51
by daWsOn_s
well at least I wasn't imagine it :)
It does do a resampling. This is an AAC song output

Code: Select all

main warning: output date isn't PTS date, requesting resampling (-44188) main warning: buffer is 44190 in advance, triggering downsampling main warning: resampling stopped after 9544000 usec (drift: -618) main warning: output date isn't PTS date, requesting resampling (-45000) main warning: buffer is 44201 in advance, triggering downsampling main warning: resampling stopped after 9543000 usec (drift: -606) main warning: output date isn't PTS date, requesting resampling (-45000) main warning: buffer is 44212 in advance, triggering downsampling main warning: resampling stopped after 9544000 usec (drift: -595) main warning: output date isn't PTS date, requesting resampling (-45000) main warning: buffer is 44224 in advance, triggering downsampling main warning: resampling stopped after 9543000 usec (drift: -583) main warning: output date isn't PTS date, requesting resampling (-42000) main warning: buffer is 41235 in advance, triggering downsampling main warning: resampling stopped after 9218000 usec (drift: -556)

Re: pitch/speed changes

Posted: 07 May 2010 18:56
by daWsOn_s
what and why does it do it?

Re: pitch/speed changes

Posted: 07 May 2010 19:05
by VLC_help
Those are just generic de-sync messages. They don't tell what is causing them.

Re: pitch/speed changes

Posted: 07 May 2010 19:32
by daWsOn_s
So I'll never know the cause? Can you try if you experience the same?

Re: pitch/speed changes

Posted: 08 May 2010 18:48
by VLC_help
You have some sample file you could share to us?

Re: pitch/speed changes

Posted: 09 May 2010 01:17
by daWsOn_s
EVERY file I could find in the world = VLC "problem" :D

Re: pitch/speed changes

Posted: 30 May 2010 03:30
by tropicalfish
Sorry for bumping a somewhat old thread, but I just wanted to say that I experience it similarly. Compared to other players like WMP or foobar2000, I can hear sort of like a pitch increase or dip that's VERY gradual. On some tracks, when the pitch "dips," it's really noticeable.
Latest version of VLC.

Re: pitch/speed changes

Posted: 30 May 2010 14:23
by daWsOn_s
finally :D I'm not crazy :D

Re: pitch/speed changes

Posted: 31 May 2010 17:15
by tropicalfish
It sounds sort of like a vinyl record rotating inconsistently. Default settings produce the same issue.

Re: pitch/speed changes

Posted: 24 Jun 2010 12:33
by daWsOn_s
Not fixed in the latest release :( very annoying bug for audio "sensitive" people. How can I officially report a bug to the team?

Re: pitch/speed changes

Posted: 24 Jun 2010 18:13
by Jean-Baptiste Kempf
trac.videolan.org/vlc

Re: pitch/speed changes

Posted: 24 Jun 2010 20:19
by VLC_help
This is hard to fix without being able to replicate the exact circumstances.

Re: pitch/speed changes

Posted: 24 Jul 2010 13:08
by babybird
None of you are crazy, I've had this problem for quite a while too. If I disable "time stretching audio" it used to not do it but I think I've begun to hear it once in a while with that disabled too in 1.1.0 and 1.1.1, but not as often. I can't remember if it did it in 1.0.5 or not with time stretching audio disabled. I only notice it with audio files, mp3 in particular. I can't remember if I've had that problem with wav or flac.

For what it's worth, Win7 Ult. x64, Intel Core 2 Quad, no OC, all stock, and the problem appears with a clean install with default VLC settings.

I don't see many posts on this, is it a known issue or are most people's ears or music tastes not sensitive enough to pick up on the pitch shifting?

Re: pitch/speed changes

Posted: 24 Jul 2010 13:31
by daWsOn_s
are most people's ears or music tastes not sensitive enough to pick up on the pitch shifting?

That's my opinion,
anyway i can assure you it happens with every format currently known, video and audio. Enabling "time strecthing audio" makes it much more difficult to feel it because the pitch is not changed, it still has the problem

Re: pitch/speed changes

Posted: 01 Oct 2010 02:20
by aldrich_lucas
I'm sorry to bump a rather old thread, but the same has happened to me on numerous occasions. If it helps, Win Vista, Intel Core 2 Duo. Anyone know a way to fix this? Disabling time stretching audio doesn't do anything to fix it.

Re: pitch/speed changes

Posted: 01 Oct 2010 13:37
by daWsOn_s
I know...apparently it's not an important bug :D

Re: pitch/speed changes

Posted: 11 Oct 2010 12:14
by Jean-Baptiste Kempf
Or too complex to solve.

Re: pitch/speed changes

Posted: 11 Oct 2010 13:59
by daWsOn_s
that too but it's the only player that does that so...