I know that the film base differs from 135 to 120 even with "the same" film in B&W, so perhaps this is normal for 120 film?
The main reason for my concern is that the files from the scanner has to be so hard processed that I get quite a lot of noise, which i suspect wouldn't be the case if the film was clearer in the base.
I don't know about prints, because I never do prints.

Maybe it's depending on developing temperature? Since I've ruled out blix and rinse, it could only be the film itself or the developing, I think. It's not likely that I've screwed up the chemicals already!