I generally keep my Carbonite map zoomed way out so I can see the whole area, but for some reason any time I go inside a cave or house, the map zooms in super close and doesn't zoom back out again after I leave the cave.

Will check this in spare time. Just be patient.

i got the same issue in shadowlands

As of 5/24/2021, I am still having this issue, especially with The Great Seal in Zandalar. I do not have the Shadowlands expansion pack (yet). I set my map to whatever size I want, but going into/coming out of The Great Seal will always resize/zoom waaaaay in on my map. The front door is usually the main crossover and zoom-in point.

I suspect that when you go indoors and the minimap scale changes, it's also causing the Carbonite map to change to the same scale, but it's not changing back when you leave. This issue occurs in most cases where you go "indoors", such as caves and buildings.

It's not just indoors but in Oribos for example, and not just when you leave the zone but when u approach aswell. And im not using carbonite mini map at all so i don't think its connected to that.

ed. I just found out after some testing this is not happening when option "restore map scale after tracking" in map section settings is unchecked (default on)