i think there is a faulty compressor preset - or output preset in compressor- or bug ( or change in quicktime documentation ) which puts conflicting information into the movie file - about the frame rate of the file.
I examined some files which 'did not play'-
and in quicktime player the frame rate shows are 24.97fps!
This is clearly not right. These are 'PAL' files and the indicated frame rate should be 25FPS - so clearly apple hasnt figured this out either.
Also in my pdf information - the time scale of the movie is wrongly indicated -
seems like compressor has some kindof bug when it is asked to convert files from one frame rate to another.
---
On one file i have which doesnt play - which i think was converted from ntsc to PAL using compressor -
For the very technical- the movie header information on one file says its time scale is 2500, its duration 11700. But the media handler says that the timescale is 2997 and the length 14040.
11700/2500 = 4.68, 14040/2997 is 4.684684 - the second ratio is not exact....