Thanks for your clever thoughts Mathias!
I think you are right. At first I thought it was NrGui to blame but now I think it's my mistake: I've boosted unnecessary low frequency content without noticing it and can't get rid of it even with highpass filtering or I would end up having no kick drum at all.
I have to go back to square one and be more accurate this time - step by step.
I think I have to adjust my brain to Nebula sounds too: so big changes happening soundwise after dried-up digital world. " The Times They Are A-Changin' "