mkvmerge - no quality loss?

[gustav32]

I have som mkv-files that I play on my WD TV-box. Because the WD TV have som synq problems with external subtitles, I want to merge the srts into the mkv.

From another topic in this forum, someone recommended mkvmerge. I went on adding the subtitle to one of my movies. The filesize was about 8 GB. The process went so fast, so I guess the file could not have been reencoded. But anyway, the new mkv file I got, was som MBs less than the origianal. I don't understand how it could be smaller, because i added the sub, so I thought the new file should be a little bit larger than the original.

So I want to be sure there will not be any loss in quality using mkvmerge before I start working with my other mkvs. And how could the new file be smaller than the original after adding a srt?

Thank you very much in advance

[Baldrick]

Nope, you wont lose any quality using mkvmerge. But check so it's the entire video so it hasn't cut it at the end.