Turned the volume pedal off in the Rig settings, to no effect. Have an FCB1010, but I don´t use it here at home; it´s connected but turned off.
Meanwhile every rig is unusable, sounds really bad. Every distorted profile is very nasal, overly and digitally distorted.
Like some kind of input or output filter is running away.
Calling customer service tomorrow.
Must be a different problem than the one I had. That fixed mine. The only other things I can think of are to check that nothing is locked, check the input setting, make sure the cabs are on for your output method. If that doesn't work, you can try a soft reset. If that doesn't work, you can take a backup, do a full reset, and reload the backup.
Kemper support will most likely ask for a backup, so they can load it and test it out. They are very fast at getting back to you. I'd get them involved at this point. They've always gotten me on the right track.