MKV audio sync problem

Discussion of advanced MakeMKV functionality, expert mode, conversion profiles
Post Reply
jeffca
Posts: 4
Joined: Tue Feb 14, 2012 1:49 am

MKV audio sync problem

Post by jeffca » Fri Jun 15, 2012 6:13 pm

:?:
I'm throwing this out there since I haven't had the chance to test it yet:

I've had several MKV's get a bit wonky when it came to audio sync. I think the worst case was City of Life and Death. The Chinese audio track kept sliding all over the place and it seems to be happening more often on other titles.

Basically, I'm watching a film and then, all the sudden, the audio is out of sync by a half or full second (not necessarily exact, but...). Regardless of player (Mac BluRay or VLC) the result is random, but the same. Use the playback slider and it really goes nuts. There is no cure for this in Mac BluRay Player (which uses the VLC engine), but VLC can offset the audio track temporally so, when this happens, I switch to that. In the case of City of Life and Death, I had to adjust it a half dozen times or more. Quite annoying. Skateland was pretty bad in this respect, too.

The reason I bring this up is that I see alerts about dropping frames for audio sync in the status window. I don't know whether this has anything to do with that or it's some other shenanigans the studios are doing to thwart bootlegging. Me? I just want to watch movies in my home theater on my Mac Mini.

For all I know, it could be the player's fault. I'll be running that down this weekend. I've backed up several Blurays to my drive and will rip MKV's of them. I'll be able to compare against disc backups ands the discs if this happens now.

A bit of praise. I got a series disc of The Wire from Netflix and one of the episodes was badly damaged by a heavy scratch. It wouldn't play in my Pioneer DVD rig or rip with any software... except yours. Took about an hour to sort out in my little DigiStor BD burner and MakeMKV. It played back flawlessly. Nice!

Thanks,
jeff

Smithcraft
Posts: 654
Joined: Mon May 02, 2011 8:56 pm
Location: Seattle, WA

Re: MKV audio sync problem

Post by Smithcraft » Fri Jun 15, 2012 10:49 pm

If the audio sync gets worse over time, then I would say that the playback software is not playing at the correct frame rate which can be fixed by changing the fps with mkvtoolnix. If it's just the same offset for the entire feature then it's an offset issue which can be fixed with mkvtoolnix.

Otherwise, your last paragraph is talking about something that you aren't supposed to be doing...

SC

Post Reply