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Question: Stuttery playhead in 10.4

I'm on a maxed out 2016 MacBook Pro 13" Touch Bar editing various projects in FCP 10.4.

At various times the playhead moves in a stuttery motion across the timeline in increments of about 0.5 seconds. This makes it very hard to do precision editing. In most cases I can make it stop på selecting a clip in the browser and playing that back very briefly, so when I return to the timeline, playhead moves fluently again. Sometimes it takes a couple of trips back and fourth from the browser. It seems like the problem usually arises when I make an edit that triggers the magnetic timeline feature. An example could be making a simple in and out point a hitting delete. This will in most cases make the playhead move in increments again. Another thing is that the timecode counter only updates in increments identical to the playhead movement when this occurs. So it definitely seems to be a UI bug, but I haven't found anybody else complaining about it.

I'm almost certain that I didn't suffer this issue on any previous versions. I've always found X to suffer from what feels as memory leaks. Best described as the feeling that after intense editing in a longer timeline the UI gets more and more sluggish after 10-16 minuts of working. After restarting the app it gets back to be speedy and responsive. I've learned to live with this but this issue with an extremely sluggish playhead really drives me nuts.

it doesn't seem to matter if my library is stored on the internal SSD, my Lacie 5 disc TB Raid or a simple USB3 drive.

After instaling 10.4 and updating libraries and discovering the problem, I made a clean install of High Sierra and only installed X. This didn't resolve the issue.

I would deeply appreciate any input or shared experiences about this issue.

Thank you.

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Mar 6, 2018 3:35 AM in response to Tom Wolsky In response to Tom Wolsky

Hi Tom.

No, video is smooth. It seems to be purely a UI issue. At first I thought it was only when I was connected to an external monitor, but it seems to occur regardless of what peripherals I have connected.

I will gladly post a video of the behaviour if it helps to diagnose?

Mar 6, 2018 3:35 AM

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Mar 6, 2018 3:56 AM in response to Daniel Alban In response to Daniel Alban

It’s very inconsistent. I ran through a bunch of projects and didn’t see it, and then I saw it in a 4K project that needed rendering, and then didn’t in a 10-bit 4K project that was graded but not rendered. Could play the video fine. Should be fixed, whatever’s doing it, but I can’t say it bothers me much.

Mar 6, 2018 3:56 AM

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Mar 6, 2018 4:01 AM in response to Tom Wolsky In response to Tom Wolsky

Very inconsistent indeed. I can't find any pattern that recreates the problem, but I do think I experience the issue more than you since you are not bothered by it. It makes it seem very sluggish and buggy to work with in my opinion. But I hope you are right and that it will be fixed in the next version (wonder when that will be!). I have made a bug report already.

Mar 6, 2018 4:01 AM

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Question: Stuttery playhead in 10.4