Strobing .mov Flash File. Why?

The designer just sent me a .mov file that was converted from a Flash file. So it is a .mov w/ embedded Flash. It is 800x600 1.3MB - Under properties it shows a flash track with format "Flash."
Using Quicktime 7.1.3 - (with the Flash option turned on) the .mov plays fine when opened in Quicktime.
However, when selected and played (Play Loop Forward) in Catalyst 4.05_m50UB_HD the file stobes at approximately 24 flashes /second.
Any Ideas?
Not having that problem with other .mov files with a "video track" and photo JPEG compression.
Thanks,
Michael