I just got 5 brand new 12-core 32GB Ram, 8TB Raid, NVidia Quadro 4000 Mac Pro's... with the intent of running CS5.5 on them without having to transcode much. But whenever I drop an h.264 clip (from a Canon 7D) onto a Blackmagic timeline, it plays for 2 seconds, and then stops. No error or anything. Just stops. Anyone have any ideas?