Thank you Mr Bukhard...
I was wrong, i didn't see the "monitor stereo" in the monitor output section page 1/9. And now it works well, and in the page 9/9 Kemper Kone, when i change the model of the kone the sound change without desactivate the cab of the rig. It was simple and i didn't see that. My bad.
Thanks a lot for your help !