Hi all,

Any help would be really appreciated as im quite distressed about this issue.
I saved up and purchased an LG 4k monitor for my mac to run the programme on, it replaces a really old 1080p monitor which worked fine but was just...old.

When playing back my projects (and demo projects) the video is hugely jerky- almost as if it were missing frames or something. When exported the movie looks fine, and not jerkiness- but its meaning that  I can't work on the project itself due to this framerate issue

For reference i'm using and LG 27UL850  and a mac mini (same mac mini that works fine with my much older monitor)

Any ideas? I thought maybe it has something to do with freesync on these modern monitors but turning it off made no difference.
I've tried plugging into my mac via USBC/Thunderbolt and HDMI and no difference. Is there a hidden setting in CTA somewhere perhaps?