Hi, your problem is with a KN5000, the service manual in on this web site go to Nigel's archive and then KN5000 the manual is there but if you have been using the KN7000 manual the KN7 is very different in all ways as the amp system is all digital right up to the last stage of amplification as the keyboard is able to transmit and receive via USB on the audio side.for your keyboard use the correct manual as all KN series keyboards have major differences between each other.
Best regards John.