FCPX Crashing on Render

Hi so not finding any love from the Apple forums.

I have this issue when I render the timeline I am getting loads of green artefacts, FCPX crashing, iMac crashed 4 times now... I have deleted the preferences several times, done a safe boot to sort out any other system issues, re-installed FCPX but it still persists. Really irritating. I can pull the XML in Resolve but sadly not all the info translates like the colour corrections and grade.

Does anyone know how FCPX renders the footage, creating the "temporary" media? I have followed the same work flow for many years with no issues. This happens on different kinds of media including FCP generated titles etc. I know it is the render that's an issue, when I slightly change a clip to remove the render and re-render that render if fine.

Wish I had more control over this?

As Luis explained from reading the EtreCheck report, there is a high probability that CleanMyMac has damaged the system, and it needs to be rebuilt.

1- Preferences, turn off background rendering.
2- Select the Library in the browser, File menu, Delete Generated Library Files, and from the resulting window, delete all render files.
3- If you ran Clean My Mac or anything similar, omg... backup your FCPX libraries, wipe that system clean, reinstall everything from scratch. Those things are a scam and will trash your Mac so badly...

Videopixels wrote: ...Does anyone know how FCPX renders the footage, creating the "temporary" media?...I know it is the render that's an issue, when I slightly change a clip to remove the render and re-render that render if fine...Wish I had more control over this?

First do what FCPX.guru said.

It's not a matter of control -- your system is somehow messed up. There is either a system-layer issue destabilizing things or a codec, 3rd-party plugin, kernel extension or other app is crashing FCPX. It's not FCPX that needed re-installing it was MacOS. Fortunately you can usually do an "in place" MacOS re-install without blowing away all your apps (unlike Windows which uses a centralized app registry). Make sure you have a complete backup before doing this.

Make sure you are not running Chrome or any browser based on Chrome like Brave. Chrome mis-uses the MacOS VideoToolBox framework and can cause FCPX to hang or crash.

If you are using any HEVC codec, with FCPX 10.4.7 and .8 on either Mojave or Catalina there is a narrow bug whereby certain codec variants can hang or crash FCPX during a render or export. If you have any HEVC media transcode those to optimized media.

To locate HEVC media you can add a codec-specific search to Finder. In Finder do CMD+F, then change "Kind" to "Other", then pick "codecs" This will add a codec search to Finder. Then repeat that but select Codecs contains HEVC, and for search scope pick "This Mac". This will do a Spotlight indexed search of metadata in all files for those using HEVC encoding.

Inspect whether you have any 3rd-party kernel extensions loaded. Any of these can potentially cause a kernel panic or even crash an app. Type this in a terminal window:

kextstat | grep -v com.apple

Run Disk Utility First Aid on all drives. To run this in update mode on the system drive you must be first booted into Recovery Mode: support.apple.com/en-us/HT201314

Rebuild Spotlight indexes on all drives: support.apple.com/en-us/HT201716

Run Apple Diagnostics. This is a lightweight test and a clean pass means nothing. However it's easy and quick to run and if it finds anything that is significant: support.apple.com/en-us/HT202731

If none of those steps work you likely need to erase the machine and re-install MacOS from scratch, then re-install FCPX. During that process do not blindly re-install a bunch of 3rd-party plugins. Those can crash MacOS, so carefully and selectively only re-install the 3rd-party plugins and effects you really need. Do this sequentially and test each one.

Great reply Joema.

Also been wondering if a plug-in might be causing this. Do you know if CoreMelt, CrumplePop, Dashwood or Pixels Film Studios can cause these issues.

I assume they all open with FCP and run services in the background. Going to remove as much as I can, don't ever get notifications to update 3rd party plug-ins would have been great to have that feature.

Will also look at re-installing Catalina... will probably be awhile before moving over to Big Sur to make sure FCPX is happy on the new Mac OS.

Videopixels wrote: ....Also been wondering if a plug-in might be causing this. Do you know if CoreMelt, CrumplePop, Dashwood or Pixels Film Studios can cause these issues...

Any 3rd-party plugin built with Apple's FxPlug 3 SDK can potentially hang or crash FCPX. That includes some of the above. This is due to FxPlug 3 architecture which runs plugins within FCPX address space.

In the future this will hopefully be fixed as plugin vendors move their products to FxPlug 4 which can enable out-of-process plugins, thereby preventing a plugin bug from "deranging" FCPX. developer.apple.com/documentation/profes..._minor&language=objc

Due to this architectural weakness you should not install plugins in a cavalier fashion from just any old company. The company should have a reputation for high quality products and for active, timely support and bug fixing.

I use CoreMelt and MotionVFX products and feel OK about those. I have some from FxFactory and I've gotten good support from FxFactory.

Another issue is the lack of standardization for FCPX plugins. There is no standardized way to inspect what plugin version, for installing, for de-installing, etc. Often each company will have unique procedures for installation, de-installation and updating.. Sometimes de-installation requires watching a video or even contacting the company to get a special "clean uninstall" tool. This is unfortunate and is a drag on the entire plugin ecosystem, both commercially and from a support standpoint. Hopefully FxPlug 4 will eventually improve this, as plugin developers gradually re-write their code.

Thanks so much.

Yeah, think it's time for some house cleaning. Will get FCPX to its most vanilla state, good practice anyway.

Appreciate the info.

In case any comes across this thread.

It looks like I have resolved this by deleting as many unused plug-ins as possible. It had nothing to do with external applications.

It seems the wild west of plug ins being forgotten and with unstable builds with newer versions of FCPX will always be there.

Yeah, every major FCPX update, you need to verify you have the latest version of your plugins. There's really no way for an NLE to do that for you. And yes, clearing out old stuff you never use is always a good idea in any app.