PSA: fix for display or preview lag on Macs with dual screens

[pkroll]

I'm posting this PSA in the hopes that people will find this from searches, instead of spending hours or days debugging, or even returning their computer as one person said they did.

Problem: Mac computers (possibly limited to M1/M2 Apple Silicon machines) have a major bug with dual or multiple monitors and certain creative or graphically demanding applications.

After Effects exhibits laggy ram preview playback. I've also seen issues with UI lag in Blender, and heard scattered similar reports from other programs as well.

Solution: turn ON Displays Have Separate Spaces under System Settings > Display and Dock > Mission Control.

I personally experienced this with a new Mac Studio M2 Ultra, Apple Studio Display, and an LG DualUp display. No configuration of ports, HDMI, Thunderbolt, etc resolved the issue, but disconnecting either monitor did fix it. This led me to the Spaces fix, and I've since seen it corraborated by other users, and Adobe employee Jenkmeister mentions that Adobe and Apple are aware of it it, as of Sep 7, 2023.

[fila.]

thank you very much, this solved my problem! 🙏

[andrewcg]

Thank you.  Turning on:  "Displays Have Separate Spaces" fixed it.  My video was playing smooth on my Dell monitor but not on my Apple Studio Display.  I've tried everything.  Including unplugging my Apple Studio Monitor for a minute to reset.  This fixed the video and a few other problems I was having.  FYI:  I have a Mac Mini with M1 chip in case anyone looks up this resolution.

[fila.]

have you tried to switch monitors' cables? how does look the video on the apple studio display? what's the behavior of it?