Mouse cursor and animations choppy in MacOS

Hi community,

A couple of months ago I purchased a 2018 Mac mini (Core i7 3.2GHz, 32GB RAM) which came with Catalina (and latest updates) pre-installed.

A couple of weeks ago I started running into a problem with the mouse cursor and animations within MacOS, it's like the frame rate of the whole machine just halved overnight. The computer is still usable, and applications don't seem to take any longer than usual to open up (I can even edit HD video within Final Cut Pro X without any major issues) but the cursor is noticeably jagged, and maximising / minimising apps is a very jagged also. Scrolling webpages suffers from the same issue.

It might seem like a minor complaint but it's incredibly frustrating just doing basic computing tasks with everything being so choppy.

What I've tried so far:

1) Downgrading to Mojave from time machine backup (no success), upgrading back to Catalina (no success).

2) Resetting NVRAM (no success)

A couple of other sidenotes:

• During that period I did use an eGPU (Razer Core X + Vega 56 graphics card) which may have contributed to the problem, although I've been using it with my MacBook Pro 2016 for about 12 months with no issues at all. Regardless of whether the eGPU is plugged in or not I still get the choppyness.

• When I first got the Mac mini I upgraded the RAM to 32GB (from 8GB). Everything ran smoothly from the beginning, so this doesn't seem to be the cause of it.

Any other suggestions would be greatly appreciated!

Many thanks :)