seen this quite a lot recently . dont know what is causing it. only affects some files - not all- in any one batch.
its not you - im trying to figure out what is causing it- at the moment the common link is compressor rendered files - in particular compressor 3. seemed to only affect photojpeg to begin with.
Seemed to happen more in files created by compressor with a timecode track- though removing this only helped with some files.
Please try to find out how your files were created or post-processed.
not everyone has seen this yet - which seems to me its something that changed in an OS or quicktime update- but im not certain.
I can make this happen on a whole set of files here. it surprised me too.
thanks