www.makemkv.com

Thor: The Dark World - 00:30:47
Guardians of the Galaxy - 01:14:32

Both of these movies, and a handful more have audio cutouts/glitches at these moments. It happens to around 10% of the movies I've ripped. It is repeatable. At first I thought it was because of the disc itself, but I tried with a friend's disc of GotG and it did the same thing. This audio issue doesn't exist if I simply watch the movie off of the disc. It's very minor, but it leads the rip to be imperfect and I'm trying to figure out how to stop it.

When you ripped these disks, were there a lot of messages about audio sync problems? You may have that turned off (it's optional), but a LOT of disks have issues with the time stamps on the audio tracks not matching the video. MakeMKV tries to correct that. It is especially prevalent in disks with "seamless branching", where multiple files are combined to make one movie.

I verified the issue with Thor - The Dark World (though mine occurs at 30:48). Also GotG. Under preferences -> General, I checked the following boxes:

Log Debug Messages
Expert Mode
Show AV synchronization messages

However, after reviewing the log (both in the application and on disk), there were no audio issues logged, yet the anomalies remain. I did 2 backups and in both cases, no errors were detected.

Well it's somewhat reassuring to see that I'm not the only one who has encountered these issues. Is there any way to only rip the audio track since I can use mkvmerge afterwards?

What settings did you use, audio passthrough (default profile) or the FLAC profile? Something else?

What are you using for playback?

I used the default settings. I used MPC and VLC for playback.

It *might* be a libavcodec bug.

Is the audio glitch reproducible if you cut a 10 to 30 second sample around the corresponding timecodes, using e.g. mkvmerge GUI?

I think Romansh may be correct. I played the section of GotG on my WDTV media player (several times) and couldn't detect the glitch. I suspect Thor would have similar results.

Wow, you are right. I tried a different player and it went perfectly. Huh.

Romansh wrote:Is the audio glitch reproducible if you cut a 10 to 30 second sample around the corresponding timecodes, using e.g. mkvmerge GUI?

In which case the above would help

Any ideas on whom should be contacted about this issue? MPC? ffmpeg?

tribunal88 wrote:Any ideas on whom should be contacted about this issue? MPC? ffmpeg?

Just provide a few-seconds sample that reproduces the issue, and I'll forward it as required.

Romansh wrote:

tribunal88 wrote:Any ideas on whom should be contacted about this issue? MPC? ffmpeg?

Just provide a few-seconds sample that reproduces the issue, and I'll forward it as required.

Ping?

Sorry. I've been buried in work and family stuff. When I come up for air, I'll try to get you a sample. I'm actually a little surprised at how few people have encountered this.

I noticed it doesn't happen with VLC v2.1.5.