FFMPEG: Change language of audio track of MKV file.

Sometimes audio tracks are displayed as “Unknown”, this might cause issues with specific software to chose the default audio track when there are multiple audio tracks in the same file.

This method worked for me so I’ll try to explain how it works.

ffmpeg -i movie.mkv -map 0 -c:a copy -c:v copy -metadata:s:a:0 language=por -metadata:s:a:0 title="Português" movie.mkv

-c:a copy -c:v copy - This will tell ffmpeg to copy the audio and video tracks without reencoding.

metadata:s:a:0 language=por -metadata:s:a:0 title="Português" - This will set language to `por` and sets the title to "Português" to the audio track 0. You'll need to figure out which audio track you should change.

And that’s it.

Any questions or doubts, write a comment and I’ll try to answer.