I'm sure the interface is not to blame. I thought about that, reevaluated every 'in' and 'out' in the control panel, checked the gain levels everywhere. Meanwhile I also tried it whith the analog inputs. It's the same.
And most importantly:if I take the interface out of the signal chain and listen through the headphone out of the kemper it is the same. Way too much bass(and maybe additional stuff that I can't figure out).
Meanwhile I performed several factory/init resets to exclude some whacky things there and bring the kemper back to factory setting. But still: nope.
If no one has an idea, I might open a support ticket.
I'm still very thankful to all of you here =)
Might be your next course of action, but hard to believe its not a setting or something else, but without a side by side test with another Kemper you won;t know. Hope you get it sorted...