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[HELP] Hybrid introducing audio delay that is not present in source material
#1
Hybrid 'Current Input Audio Information' for the source material notes Delay: 0, which is correct. The audio and video are in sync from the source.
The output however encodes a delay of -43ms, which throws off the sync.
I can manually input a delay of +43ms, which changes the delay back to 0, and the output is again in sync.
Why is this happening and how can I prevent it without manual adjustment?Please, read the 'Infos needed to fix&reproduce bugs,..'-sticky before you post about a problem.


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#2
The inserted delay is adjsuted by the aac encoder delay, which should not cause sync issues, but prevent them.
The delay is adjusted by:
a. the aac encoder choice
b. the container choice
c. sampling rate and in some cases settings in the encoder
You can tell Hybrid to not compensate the aac encoder delay by deactivating "Audio->Misc->Compensate aac encoder delay" (haven't disabled this for years, so if there's a problem let me know) before the entries in the audio job queue are created.

If you have a small sample which allows to reproduce the sync issue I would be interrested in it.
Side note: if you are muxing to .mp4 try if this also happens if you use ffmpeg as muxer since the MP4Box developer just yesterday fixed a bug regarding the muxing delay.

Cu Selur
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#3
(30.09.2021, 18:52)Selur Wrote: The inserted delay is adjsuted by the aac encoder delay, which should not cause sync issues, but prevent them.
The delay is adjusted by:
a. the aac encoder choice
b. the container choice
c. sampling rate and in some cases settings in the encoder
You can tell Hybrid to not compensate the aac encoder delay by deactivating "Audio->Misc->Compensate aac encoder delay" (haven't disabled this for years, so if there's a problem let me know) before the entries in the audio job queue are created.

If you have a small sample which allows to reproduce the sync issue I would be interrested in it.
Side note: if you are muxing to .mp4 try if this also happens if you use ffmpeg as muxer since the MP4Box developer just yesterday fixed a bug regarding the muxing delay.

Cu Selur

Small is relative but here is a 90 second clip
https://drive.google.com/file/d/11UW6dbM...sp=sharing
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#4
Thanks, got the file.
What output container format do you use? (mp4/mkv/mov/...)

Cu Selur
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#5
(30.09.2021, 19:15)Selur Wrote: Thanks, got the file.
What output container format do you use? (mp4/mkv/mov/...)

Cu Selur

Using mp4 for YouTube. I did mkv first before I found out YouTube wouldn't accept that container, but I believe A/V was in sync.
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#6
Okay, for mp4 please try whether it works in ffmpeg without having to disable the delay adjustment.
Enable 'Config->Container->Mp4 Settings-FFmpeg instead of MP4Box' before creating the job queue.

Cu Selur
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#7
(30.09.2021, 19:24)Selur Wrote: Okay, for mp4 please try whether it works in ffmpeg without having to disable the delay adjustment.
Enable 'Config->Container->Mp4 Settings-FFmpeg instead of MP4Box' before creating the job queue.

Cu Selur

Actually I may have spoke too soon - with further testing it seems like nothing I do can change the audio delay, even manually.

FFMPEG and MP4BOX have the same result. The audio is always just slightly off.

I set the delay to 500ms for giggles and it did not change the output file. 

I checked back at the MKV output and it was off as much as the mp4. 

Debug is attached. In the link is a sample out-of-sync output. Slowing it down to about 40% in VLC helps. The source is dead accurate.
https://drive.google.com/file/d/1IXPJ7Ul...sp=sharing
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#8
Like I wrote that is probably the fault of mp4box.
-> will send you a link to my current dev version with a newer Mp4Box in it.

Cu Selur
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#9
protectron, as it was requested by Selur many times in other threads: "Please do not do full quotes of posts, since it is really annoying to having to scroll to all the previously posted content. "
Simply click "New Reply" button when you post a comment:
[Image: 9thiR7c.jpg]
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#10
I installed the dev version and am pretty sure I matched all of the previous settings but am now getting a crash error.
Debug file attached.
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