Editing MPEG-4 files from Sony FX3 on FCPX

@Nathan430

Updating is exactly what caused the problem. XAVC 120FPS Clips before the update worked fine. Now they do not work at all in FCP or in Quicktime. Even though moving forward you could record in XAVC-HS to solve, it doesn't fix the issue of hundreds of hours of footage that has been captured in the past and projects that have already been in production. Happened to me yesterday. Client needed changes made to a project from last year, opened it and all clips shot in that format were now black with only audio. This is a major issue for professionals that needs fixed immediately.

So for those reading this, do not take Nathans advice and update to the latest OS. It will break everything shot up to this point in that format.

Hey there busterbboy,

Thanks so much for using Apple Support Communities.

For this issue, there is some really good insight which you can find in this article: If a media file doesn't open or play on your Mac, iPhone, or iPad - Apple Support. That article has a few troubleshooting steps that you can try which we would recommend doing since they may very well resolve this issue. Another handy resource to bookmark is this one, which goes over some of the basics of QuickTime Player: Open and play a file in QuickTime Player on Mac - Apple Support

To ensure compatibility with multiple video formats, one of the most important things you can do is ensure that your MacBook Pro is running the latest available version of macOS. This article goes into detail on how you can do that: Update macOS on Mac - Apple Support Updating ensures that the latest bug fixes and software updates are installed on your Mac which is always important in troubleshooting issues like this.

We hope that this information is helpful.

​Have a great day!

Open them with IINA.

https://iina.io/

Sony 100 fps and 120 fps XAVC-S 10-bit 4:… - Apple Community