I have this situation:

  • file1.mkv (video with two 5.1 tracks and several subtitles)
  • file1.mka (two stereo audio tracks)

I want to merge the files to a single output that has:

  • 4 audio tracks (the 5.1 original tracks and the other two from the MKA file)
  • the subtitles from the MKV

Here's the command I'm trying:

@ffmpeg.exe -i "file1.mkv" -i "file1.mka" -map 1 -map 0 -c:v copy -c:a copy -c:s copy "output.mkv"

The problem is that output.mkv does indeed have everything, but the tracks from the MKA are mute, and some players even crash when I try to play them. The other two tracks (from original MKV) work just fine.

Is there something I'm doing wrong?

  • Does ffprobe show any streams as disabled?
    – Gyan
    Apr 10, 2018 at 16:32
  • @Mulvya I'm not sure, here's the full ffprobe output: pastebin.com/4LxmSk4j
    – aur0n
    Apr 10, 2018 at 17:43
  • @Mulvya I know it sounds weird, but I think it's somehow related to subtitles. If I exclude them by manually selecting only video and audio (-map 0:v -map 0:a -map 1:a -c:v copy -c:a copy) it generated an output with all 4 tracks working ( log ). If I try to map subtitles too (-map 0:v -map 0:s? -map 0:a -map 1:a -c:v copy -c:a copy -c:s copy) it generates again two broken tracks.
    – aur0n
    Apr 10, 2018 at 18:09

1 Answer 1


why not use mkvmerge? https://mkvtoolnix.download/downloads.html

 mkvmerge.exe --output E:\output.mkv --audio-tracks 1,2 --subtitle-tracks 3,4 
 --no-chapters --language 0:und --default-track 0:yes --compression 0:none    
 --language 1:und --default-track 1:yes --compression 1:none --language 2:und 
 --compression 2:none --language 3:und --compression 3:none --language 4:und  
 --default-track 4:yes --compression 4:none "E:\file1.mkv" --language 0:eng   
 --compression 0:none --language 1:und --compression 1:none "E:\file2.mka"    
 --track-order 0:0,0:1,0:2,0:3,0:4,1:0,1:1 --probe-range-percentage 0.50

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.