MKV files streaming from ATV2

Hi,

Hope someone can help me.

I have some MKV files that I can easily put on my NAS device and stream to my ATV2.

My problem is that I need to merge SRT files to my MKV files and I have used MKVtoolnix and it worked perfectly when I am playing the new merged MKV file in VLC player but when I am playing the new merged MKV file on my ATV2 then it seems like the subtitles can’t keep up with the movie and it is only showing every second subtitle box.

Anyone got an idea of what I can do ???

I really wish to keep the high quality of the MKV files instead of converting them to an m4v file, which by the way work fine but not in the same quality.