Remuxing files to fix the audio sync problem?

I’ve seen some people here and there talk about remuxing MP4’s in order to fix the audio sync problem. I have no idea what this means and how to go about it. Is there anyone who has tried this and can give me some pointers?

  • Walter

Hello. Yes there are so many problems regarind this issue. I really hope WD makes a firmware update to play mp4 audio files better. Pretty much here is the problem:

6 channel audio files cannot be played well, they skip often. So, what you do is, install YAMB for free at

Then, in editing, you can drag your video file in, and it will parse it out. You will see the actual movie and the audio file. Make sure that only the audio file is checked off, then de-mux. This will copy on the audio file. Now you have a copy of the file which contains only the audio.

Then you will need an audio conversion software, to convert the 6channel audio file you demuxed out into a 2 channel file. Then in Yamb drag the original video file in, and also drag the converted audio 2 channel file. Then check off the video portion, and check off the 2 channel file, and un-check the 6 channel audio. RE MUX and you will have a newly created movie file without the 6 channel and with the 2 channel audio.

Sorry this is such a weird work around. Again, I hope WD can come up with an update to save us all this hassle!

Also this may be easier

You can take the ten seconds or so it will take to convert your MP4 into an MKV container using mkvmerge (and on audio select the AAC is SBR box)


Wow, that actually seems to work! For those interested, mkvmerge can be downloaded here in various formats (windows is at the bottom of the page):

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