low audio and fuzz sound with .mkv files

[blue4paper]

Hello, my friends computer is having trouble playing mkv files. For some reason the intro which is like 5 or so minutes plays fine then as soon as the opening credits come on the audio and video get all messed up. The video gets cropped and pixelated (it plays full screen and good quality on my computer) and the audio gets low and "fuzz like;" the voices barely sound out. You basically have to turn the sound way up to hear anything but even then its all distorted.

The exact same video files work perfectly on my setup which is basically the same as his.

Computer to tv via hdmi cable. However, my setup is using sound from external speakers connected to my computer while he he's using the speakers built in to his tv.

Already tried updating the media players and video/audio drivers and uninstalling and reinstalling.

info on file :

Video bitrate.: 3024kbps
Audio info....: 6ch, 384kbps

any help or ideas would be great.

thanks,

 

[-RockMan-]

Let me ask you something, are you using a codec pack ?
If so which suite is it and version number ? there maybe a few ditsy like codec packs out there that will make certain files go bonkers and crash..