MKVTools audio out of sync

[speedlimiter]

I have converted several movies from a MKV container to MP4 with MKVTools only to find all of them having out of sync audio. The first minutes seem to be in sync, but if i look at the end of the movie i can clearly see, that the picture is a little bit ahead of the audio. As i convert the MP4s for my Apple TV 2G and the iPad, i pass through the AC3 stream (if any exists) and add an AAC 2Ch stream. Both of the audio streams are out of sync. And it's always the picture which is ahead of the audio.

In the help section of the MKVTools is a hint to check the frame rate of the movie. MediaInfo reports 23.976 as MKVTools does. If i check the file with VLC it reports 23.976216. I tried to convert the movie with this more accurate frame rate, but it doesn't help.

Tried the actual beta of MKVTools with no luck. Same behavior on an other Mac.

Please help me as MKVTools is exactly the tool that i've searched.

[dizzie]

Sorry it's not working for you - very frustrating. AVIdemux now handles mkv - you might try it. If you are willing to pony up for Toast, I've heard it works well for converting mkv to alternate containers as well. You should be able to change container formats without re-encoding. For a 2 hour 720p movie, it should only take like 5-10 minutes, not 2 or 3 hours, fyi.

[emmgunn]

Hi Speedlimiter,
I've found that some files are just problematic. I couldn't tell if you were passing thru the video or not, but often converting the video track fixes things. You could also try re-encoding audio, or play around with encoding only one audio track (if you get that to work, you can always mux in a second track later). Also, run into files with reporte frame rates of 23.976 that are out of sync unless I set the fps to 25. If none of this works for you (including AVIdemux) you might also want to take a look at handbrake. Good luck.

[Venidici]

Answered a similar prob using mmg. Muxing mkv with ac3

Add the video and audio tracks. untick everything else. Have video at top of list then audio second(prob doesnt matter but it worked this way. Im not about to research it further).

Click on video file in second box from top. In the third box down i selected
default track flag : yes
forced track flag :no

Theird box down select tab 'format specific options
FourCC : DIVX
FPS : 23.976(This was the PROBLEM. It has a drop down menu for frames which i was using until i discovered YOU CAN PUT IN YOUR FPS MANUALLY)

Thats it!