I cannot use MOV files from my 1DX in Premiere CS6. The files play audio but the video is un-playable. I am on a Macbook Retina with Mountain Lion.
The files play fine in Lightroom.
Found the problem, CUDA was on but not properly supported.
That's strange because CUDA doesn't affect simple playback. If turning that off solved the issue, then something unusual is going on with your system.
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