Read my thread "found the boxed-tone bug"
The thing is, when you change something in the cabs and save the rig, there will be a different sound when you go back to the sound.
I already sent this bug to the kemper-helpline. They answered that they tried it and also realized this bug. They are working to fix it.
Till then, try to zero everything in the cabs-section. This should solve the problem so far.