Audio/video sync issues even though I'm using the "copy audio" option (.mkv, h.264)

Locutus494

Hi, I have been using DVDfab for years, and had been converting my Blu-rays to .avi files. Recently, I've started recopying everything to the .mkv format with the h.264 video codec (still running GTX 780s means no h.265, sadly) and direct copying the audio using the copy audio checkbox. With the .mkv format, I have been having audio/video synchronization issues. This doesn't make sense, since I'm not re-encoding the audio, and I'm not changing the video framerate. Pretty much every disc I copy has these sync issues; some are barely noticeable and are still watchable, while others are really bad and just not watchable. Does anyone have any help for this? I'm including a scene from one of the worse rips (Watchmen Ultimate Cut) and the log file from the session that I ripped that file in. There's just a lot of dialog in this scene, which is where the desync is most noticeable (lips not matching sound).

Video link (Google Drive): https://drive.google.com/open?id=1-NbxOA0Y_RN58WTxVe-uQB8slAjf46Ue
DVDFab log file in attachments.

october262

first- try clicking common settings - AV Codec - and switch everything to software, restart dvdfab and retry
your Blu-rays again, see if you still get the Audio/video sync issue.

2nd - try checking for a driver update for your computers graphics card.

Locutus494

Using software encoders doesn't help; I have to end up doing half of my rips with software anyway instead of CUDA because of a separate issue that has been ongoing for years: the issue where .mkv files end up with bitrates different than what is selected. So I'm having the sync issue with software encoding, too.

This sync issue has been going on for well over a year, so it's not an issue of the graphics driver being out of date.

Mona

Using software encoders doesn't help; I have to end up doing half of my rips with software anyway instead of CUDA because of a separate issue that has been ongoing for years: the issue where .mkv files end up with bitrates different than what is selected. So I'm having the sync issue with software encoding, too.

This sync issue has been going on for well over a year, so it's not an issue of the graphics driver being out of date.
Locutus494

We will try to duplicate the issue. May I know what player you used for playback?
Also, did you try to pick other audio track for backup and playback? Same sync issue?

Locutus494

I use VLC, but it plays exactly the same in Windows Media Player or anything else.

Across all the Blu-rays I've ripped, the issue happens with any kind of audio track (DTS-HD MA, Dolby TrueHD, Dolby Atmos, PCM, AC-3, as well as multiple different channel numbers, 5.1, 7.1, etc.).