Here is a short video of my issue: UE4 Viewport Movement Glitch.mp4 - Google Drive
Whenever I try to move an actor in the viewport (both with grid snapping on/off), the placement becomes glitchy and makes it impossible to place actors where I need them.
This issue is not present when the editor is first loaded up but very quickly occurs each time and there are no obvious reasons as to why.
I have been dealing with closing the editor down and restarting it for over a year now but I am finally at my wits end.