MKV to MP4 audio video progressively out of sync

[cooool]

Hi,

I wanted to convert an MKV (with DTS) to MP4 (with AAC). This is what I did:

1) Use mkvtoolnix to extract the video (.H264) and audio (.DTS) - no problems here
2) Use eac3to to convert DTS to M4A (using NeroAACEnc) - no problems here
3) Use MP4Box to mux the .h264 file and .m4a file - problems!!

After muxing, the audio and video are progressively out of sync. I checked the framerate of the MKV file, it is 23.976215.
The MP4 has a framerate of 23.976023.

Since the audio is the same length but videos have different framerates, it is causing the progressive out-of-sync.

What is the solution? How do I use MP4Box to mux it at 23.976215 FPS? Even if I use the -fps 23.976215 option, it ends up being 23.976023!

Else, how can I change the audio length?

Please help! Thanks!

[sneaker_ger]

Such a small difference should be unnoticeable (~40 ms on a 90 min movie). Extract the timecodes of the video and audio track of the source file and upload them here.