I have a
.mkv file which I want to delete one audio track from; let's call it
source.mkv. The ID of the audio track I want to remove is
1. So I issued this command:
mkvmerge -o out.mkv -a 2 source.mkv
After this I got curious and decided to repeat the same process to see if I got the same output file. So I issued the command:
mkvmerge -o out2.mkv -a 2 source.mkv
After doing this I calculated the
sha256 sum of both files and, to my surprise, they were different.
So my question is: why are the output files of the same command different?
My first thought is that maybe the video or audio track of the output files is loosing quality in the process, but I don't know why.