Video + Audio won't sync using Muxman

[efc1978]

Hi,

I have previously used PGCDemux and Muxman to split the video/audio from a video and add a new audio trackto the video, which was perfectly in sync.
I have started a new project, using the exact same process, except a different DVD and different new audio source, however when I use Muxman to combine the DVD .m2v with the new audio it's slightly out of sync...
Can somebody please explain why/how this can be out of synch when I've used the exact same process before which had perfect results?
The DVD I previously had success with was a VHS transfer to DVD, it had .mpa audio which I successfully replaced with new .MP2 audio.
The DVD which I can't get to synch was a DVD sold in shops with PCM 2ch stereo and 5.1 Dolby Digital .ac3 audio tracks, I have tried adding my new audio as .WAV and also .MP2, but both result in out of sync audio.
Any suggestions on how I could resolve this would be very much appreciated!
Thanks

[manono]

...however when I use Muxman to combine the DVD .m2v with the new audio it's slightly out of sync...

I can tell you it's nothing to do with Muxman. Did you check if there's a delay in the audio? You can check the A/V Synch for the PGC using PGCDemux. It can also occur if the DVD has advanced copy protection and it wasn't decrypted properly.

But sometimes the easiest way to fix it is to find out the amount of the delay by playing the DVD using a player with which you can adjust the delay on the fly (MPC-HC, among others) and then to remove that delay using DelayCut before remuxing with Muxman.

[efc1978]

Hi.
I took the original PCM.WAV audio file that PGCDemux made from the original DVD .VOB (I ripped the original DVD with DVD Shrink), and found the start of the first drum to 1 hundredth of a second (0secs.01), and cut my new audio file so the exact same part started precisely at the exact same 1 hundredth of a second!
So my new audio should be precisely in sync (they're also both digital an exactly the same overall length from song start to end).
I would guess it appears to be about 3 tenths to half a second out of synch (the audio is behind).
I haven't checked the A/V synch with PGCDemux, I don't know how to, I've never had any experience working with the other programmes you mentioned either, should I be able to work it out just by downloading them?, I haven't worked with video very much before....

**OK in PGCDemux I just loaded my out of sync video, I ticked demux audio and ticked demux video (I don't think they matter for this process), I then clicked "check A/V delay" and it says 0xA0 = 0msecs.

**I also just clicked on the original DVD .VOB for that song and it says one audio track is 0x80 = 216msecs and the other audio track is 0xA1 = 265msecs, however to watch that original .VOB it actually looks in sync.

I have found that cutting 0.216 and also 0.265 off the start of my new audio makes it look much more in sync, but I don't know if that is a co-incidence, how does PGCDemux say the original .VOB is off that far when in fact it is the one that plays in sync?
Also from the results I wrote above how do I tell which refers to the PCM WAV 2ch and which is the Doly 5.1 .ac3 track ?

Thanks

[hech54]

One success and the next not-so-successful.....that sounds about right.
I replace audio in video clips all of the time and a perfect match comes along around 60% of the time. I spend most of the time slightly adjusting the playback rate of the new audio in a program called Reaper.
Muxman is useless to me for most of what I do. GoldWave, Reaper and AviDemux are my 3 main weapons in replacing audio....and I only do music videos that are between 3 and 5 minutes long.

[manono]

**OK in PGCDemux I just loaded my out of sync video, I ticked demux audio and ticked demux video (I don't think they matter for this process), I then clicked "check A/V delay" and it says 0xA0 = 0msecs.

Did you set a delay in Muxman when authoring? No. So, of course no delay shows up in PGCDemux when checking the reauthored DVD.

**I also just clicked on the original DVD .VOB for that song and it says one audio track is 0x80 = 216msecs and the other audio track is 0xA1 = 265msecs, however to watch that original .VOB it actually looks in sync.

Yes, it would, as the delay is taken into account when playing the DVD.

...but I don't know if that is a co-incidence...

No, it's not a coincidence.

Also from the results I wrote above how do I tell which refers to the PCM WAV 2ch and which is the Doly 5.1 .ac3 track ?

Lots of ways. For example, with the DVD in the drive you could open DVD Decrypter, set it for IFO Mode, and then check the Stream Processing tab:

[efc1978]

**OK in PGCDemux I just loaded my out of sync video, I ticked demux audio and ticked demux video (I don't think they matter for this process), I then clicked "check A/V delay" and it says 0xA0 = 0msecs.

Did you set a delay in Muxman when authoring? No. So, of course no delay shows up in PGCDemux when checking the reauthored DVD.

**I also just clicked on the original DVD .VOB for that song and it says one audio track is 0x80 = 216msecs and the other audio track is 0xA1 = 265msecs, however to watch that original .VOB it actually looks in sync.

Yes, it would, as the delay is taken into account when playing the DVD.

...but I don't know if that is a co-incidence...

No, it's not a coincidence.

Also from the results I wrote above how do I tell which refers to the PCM WAV 2ch and which is the Doly 5.1 .ac3 track ?

Lots of ways. For example, with the DVD in the drive you could open DVD Decrypter, set it for IFO Mode, and then check the Stream Processing tab:

Hi,
Wow so PC's, DVRecorders and DVD Players etc. will know there's a sync issue on a commercially sold DVD and fix it? I didn't know that, but it definitely plays in sync in my DVRecorder/Blu-ray/DVD player, as well as clicking the ripped .VOB on my computer HD. It seems odd a commercially sold DVD would even have that sort of problem... But what would I know!?!?
Thanks

[Skiller]

It's not an issue, it's just that the video and audio streams do not start at the same time and the delay tells the playback hardware or software when an audio stream starts in relation to the video. It's quite common for commercial DVDs to have audio streams start not exactly together with the video (0 ms delay).

So what you can do is either use DelayCut, as suggested by manono, to remove any delay or just enter the correct delay for each audio stream as reported by PgcDemux in Muxman.

[efc1978]

Thanks for the info/advice/help.