Can't try this right now because my Kemper is in the rehearsal room and I am not, so I thought I'd just put it out there real quick.
According to the manual, "The high-impedance ALTERNATIVE INPUT is located on the back panel. You may find it useful in rack setups, either for connecting the instrument directly, or through a wireless receiver. It is a bit noisier than the front INPUT, but this is only an issue for guitars with a soft output level, applied to heavy distortion. Even when Input Source is set to “Alternative Input”, it won’t work when a cable is still connected to the front INPUT."
Does that actually mean I can run a cable from my wireless to the back input, and if the wireless should fail mid-gig I can just grab a cable and insert in the front input and it will work instantly (from the text in the manual it seems using the front input overrides the rear input)? Anyone try this?