Have you converted the footage to a decent editing format, or did you leave it in the format the camera uses? What are the specs for your computer? What version of Quicktime do you have installed?
I did not convert the footage, I left it in the format the camera uses. My computer has a Radeon HD 6970 video card an intel i7 core, 9216 MB RAM (via DxDiag file). I also haven't updated quicktime in a longtime so that might be the problem.
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