In our current setup, we have wireless receivers on a pedal board with a loom containing the Remote CAT5, Power and Line Input to the Kemper rack.
The aim would be to move the wireless receiver to the Kemper rack but keep the Line to the pedal board as a backup incase wireless goes down (main reason for this is to eliminate the power cable requirement for the board, as the wireless is the only thing requiring power on the board)
I don't believe there is currently a way to switch inputs using an external switch and that the Input is a Global Setting. Unless someone is able to correct me? Any possibility of it being an option in a future firmware update?