The files play, the video just freezes (or on rare occasions gets corrupted) regularly while those error messages are being printed in the status window.
I'm on a Core 2 Quad Q6600.
This is the first file from a
mkvmerge --split 5M --split-max-files 2 input.mkv -o sample.mkv:
http://rapidshare.com/files/13216963...e-001.mkv.html