Hi Saint-Francis.
It occurs on build 1299 of mpc-hc, but I went back as far as build 1043 and it still happens. Just can't understand it. At least if someone can reproduce this then I might get closer to a solution.
Here is the file (1 minute clip), about 35 seconds into the clip, the james bond intro credits start, and depending on .... well what seems like luck, you might hear the audio slowdown / speedup anywhere between 30 and 37 seconds.
Its very subtle but its definitely audible and can't be heard when the file is reconverted to any other format.
I can reproduce with or without ffdshow audio, with haali and internal mkv splitter.
Most of the time, if I seek backwards in mpc-hc to say the 20 second point, and play over the same 30-40 second region of the clip again, the problem won't be heard..... which to me might indicate some software / cache / buffer problem..... Just guessing of course.
Just hope someone can reproduce and help figure out whats going wrong.
50 MB File
http://www.megaupload.com/?d=3GZ9J6TZ