Strange FCPX 10.4.8 MOV files audio but no video

Just imported a MOV file to edit and on the timeline I have audio but the video is black, file plays but black screen.
The imported file plays fine in QT but not in FCP, checked some previously completed projects files in in FCP and the same video on timeline is black.
It seems that FCP has just stopped recognising MOV video files overnight! Is this a codec problem? not had any updates to OS or FCP so why just all of a sudden should this happen? Thank you in advance.

Could you give complete information on the media, resolution, codec, etc. Could you also give complete information on your system and drives,

iMac (Retina 5K, 27-inch, 2019)
3.7 GHz 6-Core Intel Core i5
Radeon Pro 580X 8 GB
macOS Catalina V10.15.5

It is a brand new imac running FCP 10.4.8 2TB fusion drive
I have not installed any codecs other than what came with the OS and FCP, media is HD 1920x1080 @ 25fps

Open one of the clips in the QuickTime player and report what it says in the information window.

Reboot the computer and delete the cache bundle for the library. Open the application and see if the display rebuilds.

OK, this is the info from the clip in QT
Format:HEVC (8-bit) HD (1-1-1)
Resolution: 3840 x 2160, 16:9
Encoded FPD: 29.97
Data Size: 929.8 MB
Data Rate: 39.44 Mbit/s
Current Size: 3840 x 2160 (Actual Size)
I think I have found the problem but not sure what it means or how to fix it (I'm a newbie)
When I drop that on the timeline the clip is black, no video but audio plays. I converted this same clip using QT to 1080p didn't check the 'USE HEVC' the exported file works on the timeline, just tested the same export checking 'USE HEVC' and the exported file is black (no video) on the timeline. So HEVC format is the issue, why now, I have been using footage from this camera before no problems, also all my other projects which were fine are now black on the timeline, where did the ability to see / use HEVC go overnight? I may need to edit my old projects so what can I do to see HEVC files again? Thank you

retepnikrap wrote: .....So HEVC format is the issue, why now, I have been using footage from this camera before no problems, also all my other projects which were fine are now black on the timeline, where did the ability to see / use HEVC go overnight? I may need to edit my old projects so what can I do to see HEVC files again?...

When it formerly worked, what version of FCPX and MacOS were you running? In general it should work now in FCPX on the latest versions. However there are many "flavors" of HEVC, all internally different. What camera is this from?

Starting with FCPX 10.4.7 there is a narrow HEVC stability issue which affects some versions, but I've never seen it cause black video, rather it hangs or crashes FCPX.

What happens if you transcode one of the black clips to optimized media? In the Event Browser right-click and pick transcode.

SOLVED
I deleted the FCP preferences, restarted and now everything is fine again. I guess the first thing you do when you have any problems with computers or software is reboot!

For any and every FCPX issue, try the standards first.

1- Turn off background rendering.
2- Delete all render files for the Library.
3- Boot into Safe Mode (Cmd-R) & run First Aid on all drives.
4- Delete FCPX preferences.

Hi There, I have the same problem as retepnikrap, I've imported a series of HD clips, the first two are perfect, with sound and video, and 5 following are black with only sound. When I open them with QTime, the same clips look perfectly ok, I've imported them in Imovie, also there no problem,. I've deleted the FCPro prefs, and also after that action, FCPro only imports the sound, don't know what to do next... hope to get this solved, because I need to finish the project.

Please give complete and exact details of the media files to start.

Imported into the browser? Is that where you’re setting the problem? Or something else?

What OS are you using?

Media files are QT mov 1920x1080/codecs: AAC, Timecode, H.264, they appear in the browser without video, but with sound, also when I copy them to the time line. Final Cut Pro: 10.5.1 Macbook pro: mac os 10.15.7

Do you have Chrome installed? Uninstall it completely and reboot.

Yes I have chrome installed, does it interfere with FCpro?

Uninstalling Chrome solve a couple of issues for me.

So I uninstalled Chrome, restarted the computer, and still the same result.  Weird is that the clips are saved in the "original media folder" and are fully ok, I can play them with QTime, no problem, but as soon as I load them into the FCP browser, they only show sound and no video.

This is the error message I get when I try to relink the imported clip... BUT, when I close the library, open a new library, and import the clips in an new event, everything seems to work fine.  Strange.

luklouis wrote: So I uninstalled Chrome, restarted the computer, and still the same result.  Weird is that the clips are saved in the "original media folder" and are fully ok, I can play them with QTime, no problem, but as soon as I load them into the FCP browser, they only show sound and no video.

Reset FCP preferences if you haven't already done that. Item #11 on this list:  support.apple.com/en-us/HT203477

If that doesn't fix it, verify you are on Apple Pro Video Formats 2.2.0. That is checked in About this Mac>System Report>Software Installations, scroll down to Pro Video Formats, latest version on Catalina is 2.2.0.

If not on that version, you update it using System Preferences>Software Update.

Since you are on FCP 10.5.1 and Catalina 10.15.7, normally the clip should play video in FCP if it plays in Quicktime Player.

Try creating a new test library, reboot the entire machine, import that one clip to FCP and see if it plays video, not just sound.

Yes, I tried in a new test library, and it functions, don't understand why it doesn't work in the other library...

Out of curiosity, Joe, in Big Sur there is no "Pro Video Formats" in that software section. So in BS how do you verify the PVF version?

luklouis wrote: Yes, I tried in a new test library, and it functions, don't understand why it doesn't work in the other library...

Based on the previous error message you posted, it's possible a prior relink attempt altered the project or event metadata for the linked video files and they will no longer play properly. Normally there are many safeguards in FCP to prevent that. It rejects a relink for various incompatibilities, including filename, extension, duration, audio config, etc. However the fact it's rejecting a relink to the original files may imply something somehow forced a relink and now the files won't play properly.

You can examine the project frame rate as indicated by FCP in the project inspector, then compare that to the frame rate of the current non-playable clip, then compare that to the new clip you're trying to relink.

For the latter two, don't rely on what FCP tells you about the frame rate. Do Reveal in Finder, obtain the clip on disk and use the 3rd-party utility Invisor to inspect the frame rates and other metadata. The metadata including frame rate, audio config, timecode, duration, etc. should be identical between the black clip and the new clip you're trying to relink.

apps.apple.com/us/app/invisor-media-file...or/id442947586?mt=12