Map device 6th slot (bug?)

I know that might be a schizo theory but after I completed t17 map and got 6th slot in map device I stop getting any rare content on my t16 maps. Before I was getting like 1 Black morrigan in every 5-10 maps, and Starfall crater every ~20 maps or something (might be lucky). But after that I got nothing in 100 maps, just regular mobs, crater don't spawn etc. (I have full beast and Verisium atlas + scarabs). I heard many people was saying that some slots in map device were bugged (like scarabs don't work/consume) and I just wanna know that everything is ok and I am just unlucky. Hope some dev give a respond