Please keep in mind that, when you ask our software to play an audio/video file, our software just forward the requirement to the operating system. In other words, our software says "Hello Windows (or MacOS), please play the following audio/video file". Then the operating system use the installed codecs* to decode and play the media file.
When the media file is not played well, or when the computer crashes when playing the media file, the problem comes from the codec.
Again, our software does not play the media file ; it just asks the operating system to do this job.
*What is a codec: http://en.wikipedia.org/wiki/Codec
We suggest to use the following free codec: http://www.free-codecs.com/download/k_lite_codec_pack.htm