That sounds strange. Those monitors wouldn't be P2715Q would they? Those monitors caused an issue when the multi stream transport option was enabled. Disabling MST got previews working as expected.
the monitor is an HP Z32x. but it happens on dell as well.
Talked with support and they told me something corrupts the cache and told me to remove all plugins, and delete all cache. and give it a go.
i can't keep on doing it since i need the plugins for work.
You can do it as a troubleshooting step though. If it still has the problem without your plugins, you'll know they're not the problem. If it stops, great! Then we just narrow down which one it is, by installing some of your plugins and testing until you find the one causing the problem.
Are you still facing this problem? If not, let us know how you solved it. If so, please let us know so we can assist you further.