14 Replies Latest reply: Dec 31, 2012 12:59 PM by riesje
Darfuria Level 1 (0 points)

I'm having a frequently (but still intermittent) issue where FCP X crashes when rendering a video (at around 12% completion) when FCP is set to use optimized/original media. If I render using proxy media, the crash doesn't occur, but obviously the exported file is low resolution.


Once FCP crashes, the project tends to become corrupt and the application will crash again upon launching unless I remove the project.


I'm using a 2010 2.4Ghz i5 MacBook Pro with 8GB of RAM, and a FW800 scratch disk.


  • I have successfully edited & rendered 50+ videos of 1080p videos. Neither the type of source footage, length of projects, or my workflow have changed.
  • I was using 10.0.3 prior to upgrading to 10.0.7 - I didn't have any problems using that. I've perhaps successfully rendered 40% of my projects since the upgrade.
  • I have moved the events & projects to different drives
  • If I remove a project after a crash, the application runs smoothly and I can scrub through the event media
  • If I'm using proxy media (which is what I edit with), there's no issue. I can also render proxy media
  • I've used Digital Rebellion Housekeeper, QuickFix, and Project Repair - no corrupted projects were detected even when FCP is crashing upon launch
  • Crash Analyzer reports that 95% of the crashes are due to Corrupt Thumbnail Cache. I have deleted this many times, and I edit using the simple clip view (no thumbnails or waveforms). The others are due to motion effects - the only ones I use are fade transitions, and occasionally speeding up video. Nothing third party.
  • I've deleted and re-imported event media.


I'm kind of confused as to where to go from here. The problem seems intermittent, but it's getting worse. I had a project that crashed when rendering, and FCP wouldn't launch until I removed the project. After that I managed to edit & render another project with no problems. Then the project after that crashed during rendering and caused the same problems. The source media from these projects was shot on the same day as other clips that have been successfully edited & rendered.


Any tips welcome!