Great
I just got a reply from the company where I bought the Rokits, they think that from what I told them, it sounds like the speakers are somehow broken. By now I'm not sure they are, but to make sure I'm gonna send them over to be checked. But I guess there's nothing wrong with them.
Other than that... maybe I'm just really bad at dialing in sounds in the Kemper, everytime I try to get a good high gain sound (doesn't matter if Marshall, Peavey, Mesa Boogie), I always get these unpleasant sounds that (to me) sound like fuzz/fizz in the higher mid to high frequencies. Tried to scoop those frequencies out mostly ends up in destroying the tone... Or maybe it's my guitar (ibanez prestige rg 2570), I can't really tell.
/Edit: Just ran into this thread: Trouble with high gain sounds
This is probably the exact same problem that i have (High gain sounds with trebly guitar pickups + FRFR speakers), so tomorrow I'm gonna play around with pre EQs and stuff.