Choppy video while importing or preview but works fine in iMovie

Hi!

I am new to this tool. I have been using iMovie for while but wanted to try this out. So I am trying to import video clips but it imports choppy also when I try to look at the preview it shows choppy as well.
I am able to look the preview in Mac Folders and also I am able to import it in iMovie.
The source of this video is GoPro and its 4k video.
Some of them video is already imported and some not. Not sure what’s wrong with that .
I also tried to restart the Mac but looks its only these videos has this issue.
What should I do in this case.

Thanks

This is not a suggestion. You mislabeled this thread. Please change the category to Help.

You don’t give any specifications of the computer you are using (CPU, RAM etc.). Does it meet the minimum for editing 4K videos (see: Shotcut - Frequently Asked Questions)?

Check this out