Problems Playing .MKV Files

I have a movie in .mkv format that plays from my external HDD connected to my ATV. The problem is during playback; the movie intermittently pauses so often to the point where it is unwatchable. The movie is 1080p HD. Can anyone please shed some light as to what I can do to fix this?

I’m sorry if this question is a repost.

Thank you in advance!

i thought it only played 720p

The AppleTV will support files up to 720p, with max bitrate of about 5Mb/s.

M<y MKV File is 720 and it wont play either. Well, it will play but it is very, very, extremely, unwatchably choppy. What can be done?

You can get the Broadcom Crystal HD card, and add to your AppleTV.
This card is supported by XBMC under AppleTV, and will decode both your 720p and 1080p content.

You will loose wireless, since this card will replace the wireless card on your AppleTV.