Sound Out of Sync in MKV file

[cottage]

I have a couple of MKV files and the sound is slightly out of sync.

I have found a link that describes a method to fix the problem. It uses a the command line in mkvmerge.
"$ mkvmerge -o MyVideo_FIXED.mkv -y 2:-100 MyVideo.mkv"

I'm still relatively new to video editing and have mkvmerge GUI. I can't see any way to complete this task in the GUI version (mkvmerge gui 6.0.0) and I'm still trying to figure out how to issue the command line instructions.

Am I missing something? Is there a way to delay the audio using mkvmerge gui?

[Hoser Rob]

Assuming you're having this problem with all .mkv files:

I don't know what software you're using to play video on but any good program will let you adjust audio delay when playing. That seems much simpler than what you're talking about.

mkv files with h.264 video are harder to play than divx or xvid avi's. What is the bitrate and resolution?

I've had sync problems in the past playing high bit rate h.264 video on my i3 based laptop. Which is pretty much middle of the road in general, wimpy for encoding. You wouldn't want to edit 1080p video on it.

But running smplayer with a decent size cache in kubuntu it works excellent. I have a .mkv file that's 1080p with over 10000KB/s bit rate. It'll play flawlessly.

I'd strongly suggest avoiding players without a cache setup capability (are you listening, vlc developers?) on low to mid performance hardware. It makes a huge difference.

You may have to go into your player's settings and make sure frame drop is enabled.

[cottage]

Thanks Hoser Rob,

I'm not having trouble with all MKV files. I have a new Happauge HD PVR and I'm recording programs from my satellite receiver using Arcsoft TotalMedia Extreme 2 in m2ts format and then editing out the commercials with VideoRedo and saving them in MKV format. Most but not all edited programs have audio sync problems. I'm still working with other recording and editing formats to see if I can eliminate the problem.

In the meantime, I have a few edited programs that I'd like to fix.

I'm playing the videos on a WDTV media server and it doesn't have the option of adjusting audio timing. Even if it did, I don't want to fuss with this every time I play the video.

When I play the video on my computer (usually just for test purposes), I use VLC. I have used VLC to adjust the audio timing. However, I need a program to permanently change the audio sync. That's what I found in another forum post. It was suggested that mkvmerge can do this using the command "$ mkvmerge -o MyVideo_FIXED.mkv -y 2:-100 MyVideo.mkv". I'm still working on it but I haven't figured out how to issue the command line. I have the mkvmerge gui and can't see how to do this in the gui version. That's what I'm looking to do.

In answer to you question, here are the specs of the video that I'm currently working on:
Video
5813 Kbps, 1920x1080
Audio
384 Kbps, 48.0 KHz, 2 channel AC-3
Other videos have different specs.

The computer that I'm using is and Intel Core i7 3.4 GHz with a SSD. I have no trouble playing anything. The WDTV also plays all video perfectly (except when the source file has a problem - like my audio sync)

[cottage]

OK. I admit to being a Dumb A$$!

I figured out how to do it in mkvmerge gui.

All I had to do was highlight the audio file in mkvmerge gui and the Audio delay option became available.

I input 100, clicked on Start muxing and presto - 8 seconds later I have a perfectly synced file!

Sorry for the useless post.

[hello_hello]

Almost every time a player's need for a "cache" is mentioned I've pointed out VLC still has a setting for a local file cache, it's just been moved to a different place in VLC's options, but the apparent belief it's no longer there appears to be having a reverse-placebo effect.

I'd imagine all media players use a cache. Even the one in my TV does. It must, because when playing video from a hard drive, the hard drive activity light only flashes briefly once every five seconds or so.