LinuxMCE Forums

General => Users => Topic started by: scorf on September 21, 2007, 06:08:23 am

Title: Audio not in sync with DVD and/or ripped DVD videos
Post by: scorf on September 21, 2007, 06:08:23 am
My audio (when playing either ripped DVDs or DVD drive based videos) is slightly off.  It seems a little worse when playing DVD's.  By slightly off I mean fractions of a second, but noticeable by all in the house.

Audio is in sync when watching both live and recorded Mythtv.

Can anyone help or point me in the right direction.  I'm (pleasantly) surprised to see this isn't shared by many.

Asus M2NPV-VM
Dual core AMD
Analog audio out from the motherboard (I have the digital out, but not in use yet)
HD component out from the motherboard
1080i
Plasma: Panny
Title: Re: Audio not in sync with DVD and/or ripped DVD videos
Post by: scorf on September 22, 2007, 07:46:49 pm
Switched from analog/stereo to digital/optical -- no help.   Still don't know why my audio is out of sync.   :(
Title: Re: Audio not in sync with DVD and/or ripped DVD videos
Post by: 1audio on September 23, 2007, 07:04:26 am
Lipsync is a common problem with many digital video systems. Many people are not sensitive to it until its pointed out, then they are really bothered by it. I was at a seminar with several major mixing engineers from Hollywood. they all complained that its not well managed.

Is the shift constant or changing from disk to disk? Can you tell? The published sensitivity to this is 20 mS but I'm not satisfied with that number. . .

There are technologies coming to improve it (HDMI 1.3 lip-sync has mechanisms to sort this out IF they are implemented right) For now there are adjustments in Xine for fixing this but they are not readily available. On a keyboard "n" and "m" should adjust it. But since Xine in LMCE has been majorly tweaked I don't know if they work. It would be worth a bug report.
Title: Re: Audio not in sync with DVD and/or ripped DVD videos
Post by: scorf on September 25, 2007, 05:34:28 am
1audio -- do you see this with your implementation(s)?

It seems pretty constant from disk to disk.  It's so subtle that most don't notice until I point it out.

I can live with it... although, it's just another straw on the camel's back so to speak.  The good still outweighs the bad.
Title: Re: Audio not in sync with DVD and/or ripped DVD videos
Post by: 1audio on September 25, 2007, 08:11:18 am
Yes, its its not consistent. I'm watching KVille and its consistently inconsistent.
Title: Re: Audio not in sync with DVD and/or ripped DVD videos
Post by: golgoj4 on October 25, 2007, 02:03:21 am
Anyone figured out a solution for this yet? I would like to rip the dvd's but this is killing me. As a former sound mixer, sync issues are a killer for me.

Title: Re: Audio not in sync with DVD and/or ripped DVD videos
Post by: golgoj4 on November 05, 2007, 08:07:15 am
not sure if this is related, but I found this while trying to track this problem down on the interwebs.

http://ubuntuforums.org/archive/index.php/t-338191.html (http://ubuntuforums.org/archive/index.php/t-338191.html)

maybe when the next update is fixed it wont happen? xine player is used locally in these situations so maybe its this library?

the dumb part of me wants to try and fix it manually. the smart part of me knows i would have to be lucky to...
hmm ;)
Title: Re: Audio not in sync with DVD and/or ripped DVD videos
Post by: golgoj4 on November 20, 2007, 09:07:35 pm
ok, does anyone know if I would break my current linuxMCE install if I follow the instructions in the link above on fixing the a/v sync issues?
Title: Re: Audio not in sync with DVD and/or ripped DVD videos
Post by: 1audio on November 23, 2007, 09:11:47 am
Xine has been customized for LMCE and you will have a mess on your hands if you muck with it. I hear that Xine will be replaced in the next release any week now so just wait.
Title: Re: Audio not in sync with DVD and/or ripped DVD videos
Post by: golgoj4 on November 23, 2007, 05:51:19 pm
Xine has been customized for LMCE and you will have a mess on your hands if you muck with it. I hear that Xine will be replaced in the next release any week now so just wait.

thats what I decided to do. Im not qualified to go messing around with the guts...yet  8)
Title: Re: Audio not in sync with DVD and/or ripped DVD videos
Post by: MrJohnBravo on December 26, 2007, 03:58:20 pm
Count me in on another one of those having this issue. The offset is not large ... but it is noticable. IF Xine is the issue, does ANyone know when the new 7.10 release is going to be errr... released? Also if Xine is being replaced ... what will be the replacement?


MrJohnBravo

Ohh.. mama!!!!
Title: Re: Audio not in sync with DVD and/or ripped DVD videos
Post by: hari on December 26, 2007, 06:32:09 pm
Xine has been customized for LMCE and you will have a mess on your hands if you muck with it. I hear that Xine will be replaced in the next release any week now so just wait.
as far as i got it for now the xine wrapper simply uses libxine without modifications. Xine won't be replaced for now. Mplayer was added as an additional media player.

best regards,
Hari
Title: Re: Audio not in sync with DVD and/or ripped DVD videos
Post by: MrJohnBravo on December 27, 2007, 09:54:40 pm
is mplayer any better with sync issues?

MrJohnBravo

Ohhh MAMA!!!
Title: Re: Audio not in sync with DVD and/or ripped DVD videos
Post by: golgoj4 on December 31, 2007, 04:00:53 am
Any news of this problem being fixed in 0710?
Title: Re: Audio not in sync with DVD and/or ripped DVD videos
Post by: jonsnipes on January 10, 2008, 04:02:56 pm
im having a very noticble difference..  like watching old jackie chan movies...  i tried playing the files through xine and mplayer on kde and the sync problems arent noticible..  perhaps lmce is causing the delay??
Title: Re: Audio not in sync with DVD and/or ripped DVD videos
Post by: Andy on January 10, 2008, 04:08:00 pm
I'm also having this issue when I have 0704 installed. However, 0710 beta 2 does not seem to have the same problem on my system.
Title: Re: Audio not in sync with DVD and/or ripped DVD videos
Post by: Blackhat on March 21, 2008, 03:36:05 pm
I'm having this issue as well.

Interesting sidenote (I thought anyway).  I have a HDMI vid card and run the connection through a Onkyo 805 receiver.  This is just for testing as a MD will eventually be connected through the Onkyo with SPDIF surround sound.  Currently I'm running a stereo to RCA adapter to the receiver.  I noticed the video is a little faster than the sounds (mouth opens, count to 10-20ms and the sounds hits).  This confused me because I was always under the impression that the video was supposed to lag, not the sound, when using digital video.  I figured, "No problem", and went into the receiver setup and changed the delay from 20ms to 0ms.  Everything looked great, but it started de-syncing again after a short amount of time.  I double checked the delay on the receiver and all is still where I left it.  So either a) I never fixed it and missed the smaller delay or b) something got confused again.

Also, I tried HDMI & SPDIF from my laptop w/ WinXP and there is no sync issues.  Dunno if that's windows or the combination of digital inputs (rather than mixing digital vid and analog sound).  I did notice, however, that the sound coming from the laptop speakers is out of sync (or Phase if you're a real audiophile) with the rest of the setup.  Again, the 20ms or so delay.

I'd be interested in hearing which way it's desyncing for everyone else.  Is the vid or sound faster?  Also, what inputs everyone is using.  I know some new devices have A/V sync controls (like my receiver).

For reference, my setup is:
Video
HDMI vid card -> HDMI input on Onkyo Receiver -> HDMI input on Mitsubishi Projector
Sound
Stereo output on Hybrid Core -> stereo to RCA adapter -> receiver RCA L/R input -> speakers.

Hope this helped!
Title: Re: Audio not in sync with DVD and/or ripped DVD videos
Post by: itspac on March 25, 2008, 02:48:55 am
Just to fill in. I've noticed this on DVD but not avi divx files. I too tried to use the synce on my onkyo tx-sr605 receiver, but I am using SPDIF via coax to the receiver.

so ...
video
HDMI video card -> HDMI input on Onkyo receiver ->nHDMI input on Sharp aqous TV
sound
SPDIF coax on hybrid core -> SPDOF coax in on Onkyo receiver -> speakers
Title: Re: Audio not in sync with DVD and/or ripped DVD videos
Post by: colinjones on March 25, 2008, 06:53:20 am
Blackhat - btw, the video can either lag or lead, either is possible as it is almost always to do with timing as the streams get demultiplexed, although it is often usually one more than the other. And out of sync is different from out of phase. What you are describing is out of sync. Out of phase would be manifested in a v different way, effecting the quality of the sound but not in a way that you would be able to detect a delay with your ears.

Its interesting that others are commenting on DVDs displaying this as well. If the rip is just the straight data from the disk, without re-encoding or re-multiplexing, yet there is still a difference in the delay between disk based on DVD based, that might suggest a problem with xine de-multiplexing the stream on the decode side. If DVDs were fine and video files were not, then that is more likely to be on the encoder side of things. If it is consistent, there are options for things like xine to introduce a static delay so you can compensate. Although I have not played with it. Another thought is, is the delay varying as the media plays - specifically getting longer and longer? Or perhaps even getting longer, then having a light audio drop, and coming good again for  while? That could be indicative of frame rate conversions such as a pull down - that causes alsorts of problems with sync when converting from film to 25/30/50/60fps...