Having an odd video problem. Working off of an external drive, and I have suspicions that someone improperly ejected it while I was rendering.
My video, which was captured in the ProRes 422 format, plays back with significant corruption. Everything is green, full of static and bars, and jumps around (even into other video clips...). The audio works fine. Playback in FCP is always bad, even on 2 other machines.
The weird thing is I don't think the video is damaged significantly. The source files on the hard drive play fine with the spacebar preview. If you convert the sequence to a non-prores format and then render, it's fine. When you export a clip, even though it looks corrupt during playback, the export is clean and fine. Reimporting the source clip into a brand new project does not fix it. Copying the source clip onto the internal drive and THEN importing it, does fix it.
Am I right in thinking the hard drive now has some kind of error? I'm currently back it up.
Try trashing your renders files (use the render manager) and re-render. Also if you suspect issues with your hard drive, Disk Warrior should be able to fix any corrupted directory and folder structure issues.