The Ability to Scrub Video Breaks Randomly

I've been making youtube videos for the past 2 years and this problem has been happening. It is super annoying because the only way I've been able to find to fix it is to reboot the whole computer, which is a hassle when you have lots of stuff going on.

Also this problem affects iMovie and Final Cut Pro at the same time.

Here's what happens. I'll be using the computer and suddenly the cursor will instantly jump to the top left corner of my screen, which activate Mission Control. The cursor doesn't travel to the corner, it just abruptly appears there from whereever it was.

And that's it, whenever that happens, I know I'm done editing video for a while. Once this happens, you can no longer hover the cursor over a clip in either editing app to see the video in the preview section. You have to actually CLICK on the timeline to update the preview.

That doesn't sound like much, but it actually makes it impossible to edit videos.

So I reboot. And it may not happen again for days, or even weeks. Or it might happen again an hour later.

I'm on Ventura now but it was the same in Monterey and I believe Big Sur too, though I'm not sure.

I can't tell you if the problem was around before that because I didn't do much video work before then.

My Mac is a 2018 Mac mini with lots of RAM and storage space. I don't have very many apps running at once. Activity Monitor, an IRC app, BBEdit, Safari, Messages, Mail. I don't run any sketchy or questionable utilities or software that does anything unusual. The most unique thing about my setup is probably that I have three monitors connected.

I've posted this problem before but nobody ever has any ideas. But I'll keep posting, I can't possibly be the only person out there experiencing this. It seems to be some kind of problem with the OS itself, since it affects iMovie and Final Cut together. That suggests the problem is some kind of glitch in the underlying API. If I could even just reset it somehow to fix the problem without having to reboot, that alone would be a huge win to my workflow!

If you have any ideas about this, please let me know!