MacOS Catalina mouse/system hiccups when external monitor connected via Green Cell USB-C Hub I saw past posts about this issue but it's still hitting me on the current MBP 2019.
I'm using external iiama black hawk external display monitor connected via Green-Cell USB hub

Whenever I connect external display, the computer seems to stop every couple of seconds - the mouse freezes for 0.5s, terminal also - that's very irritating.
Somehow it seems, that I can get rid of this behaviour by changing the connection order of the external monitor but also not always.

I don't see any drivers/firmware to be downloaded, anyone having the same effect and has any workarounds?
Obviously plugging and unplugging in the right order until it works is quite irritating...
It turned out to be a broken Green-Cell USB hub.
When I changed it to the newer model it works perfectly fine!