Help understanding choppy stream from my NAS to iPad to TV

I'm a bit ignorant on this subject so please educate me.

I have a Buffalo NAS where I keep my movie files. I stream the movies to my iPad 3 and then Airplay push them to my Pioneer HDTV (720P) via Apple TV 2. I have the latest Airport Extreme for my router.

The NAS is in an adjacent room about 20 feet away from the TV room (which has the connected Apple TV and iPad).

In many cases the video quality is excellent. But for other movie files it is choppy and unviewable. Last night, I took a movie that was unviewable on the iPad and wirelessly watched it on my laptop without any issues. Some details on the movie file: 3.5 GB 720P blue ray MKV. Codec H264 MPEG-4 AVC. Resolution 1280x536. Frame rate 23.976215

And recognizing that my iPad and Laptop have different connection rates, here are the details I pulled from the Airport Extreme on these clients:

Device Rate Signal

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iPad 52 b/g/n -67
Laptop 240 a/n -71
Apple TV 65 a/n -64


So why do some movie files play flawlessly off the iPad to TV and others don't? In my layman's terms, is it related to the 3.5 GB MKV file....ie, am I trying to play a movie too rich with info and my bandwidth can't handle it? Is my only (and simplest) solution to focus on the file/format?

Thanks!

Vlad

I stream from the NAS to iPad using the apps GoodPlayer or 8player to play the MKV files. With MKV files, I'm using Airplay Mirroring.

Is the suggestion that the performance an issue with the Apple TV, and nothing to do with the files, despite the fact that many movie files play flawlessly?


Vlad