Hum eliminators actually make it twice as bad. I tried it between the guitar and KPA input yesterday. It's just more horrible
You need place it after the Kemper output, before whatever it's going to. I have this; Pyle hum Eliminator. But single coil pickups will hum and if you are near any light dimmers, that will make things hum. Turning the volume down on the guitar will stop that. I got the hum eliminator because I was fine until I got to a venue then it would hum/buzz, and through IEM's its not too fun for the band. It stops the buzz the guitar volume doesn'.