Removed all third-party QuickTime components to ensure that none of the alternative movie plug-ins that are said to be incompatible with QT7 are in the folder, and upgraded (and PAID for) to QT7. The video is much smoother than QT 6.5.x, but there were NO SOUND! None of the footage I have will play sound, whether it be MP4, MPEG1, MPEG2 or plain old Sorenson 3 MOV. Immediately downloaded QT6 Reinstaller, and went back to QT6. Now movies play back just fine again. Sad.