What is happening to my first/bottom layers and overhangs ?

[IgotAquestion]

Hello everybody,I recently started using a new filament from Ender (before that Geetech). My bottom layers are always getting bumpy but nothing else is, since I've started using this filament. I looked on the internet to find a similar problem but they were all generally adressing flow-rate or the distance to the bed (bed leveling). None of that seems to be the problem in my eyes since the problem only occurs on bottom layers (see pictures "top" and "bottom") with this filament. I know that on overhangs the surface usually isn't as smooth as a top layer but the bottom layer edge is also very incosistent in thickness. I dont know if I'm missing something in the big picture. I would really appreciate it if somebody who has dealt or knows about this could help me. My Printer: CR-10s, 0.4mm nozzle, 1.75mm PLA-filament (white) Software: TH3D Marlin U1.R2.A3Kind regards Alex from Germany