why is this file causing problems?

[raspberry_pd]

Can you log in to the console via SSH? If so, please run this:

Code:

/opt/vc/lib/tvservice -a

And see if you get a line returned that includes AC3.

In general with 1080 resolution files, the Raspi chokes on the HD audio, not the video. If your display or receiver supports AC3, XBMC will pass that audio to the display untouched and all should be well. If not, XBMC may be trying to decode the HD and then mix it down to 2 channels. The Raspi's CPU cannot cope with this. For more details, see this post of mine (under another identity):

http://www.raspberrypi.org/phpBB3/viewtopic.php?p=249621#p249621

Other possibilities could be a weak or under-powered WiFi setup. Are you using a wired or wireless connection? Or is the file being read off USB?