How to play MKV file

Last week I downloaded a 4.6 GB Inside the living body ( National Geographic ) file through a torrent site. The file turned out to be a MVK extension file and it didnt play in all the players.

After doing a lot of google search I downloaded the matroska codec file from the official site. Now the file plays under media player classic , but there is a intermittent break after every few seconds in the video and audio both. The intermittent break happens at various intervals each time I play it afresh so I dont feel that the file is corrupt or is broken.

I tried core player , VLC but all of them give me the same result.

Can anyone let me know what could be the problem.