Tank threatning in the world

Server: Dry Tree
Name Amiviati

Hello!

Im not sure if this is an bug or just op threat mechanic, but I have notice several times when I as tank are out in the world and in an elite area with ancient or three folks etc and fight 1-2 elite, all of the sudden there are coming elites from all wide range around me about 5-7 elites + 3-4 normal mobs.
It also happens the floor under me I have experienced in some way I aggro them aswell, im not sure if its me using defiant stance.
And it aggro all the mobs 100m away and the floor under me aswell.

But I have also experience when fighting in an house, mobs on the top floor and outside are just running inside and attack me while I fight 2-3mobs inside.

Anyone else experienced this?