Livecode 7.0 Can't Play Video on Macs

[Ray]

When I do the following on my Mac OSX 10.7.1 running Quicktime 7.7.1 I 
hear the audio but I can't see the video.

I drag a player object to a new main stack and change the source from 
the Livecode's Sample.mov file to Apple's Sample_iPod.m4v movie or any 
other .m4v file.  Playing it gives me audio but no video.

If I choose the edit tool in Livecode while the movie is play suddenly 
video plays.  Return to Livecode's browse tool and video stops while 
audio continues.

This is no problem at all in Livecode 6.5.2 using the same platform, 
same system and same Quicktime version.  It's also no problem on my 
Windows 8.1 system in either version of Livecode.

Is this really a bug or am I missing something?  If it's a bug does 
anybody know if it's been reported?