Mk II has low signal output

[absent]

Howdy once again;

My MK II seems to be too quiet. It's not just a voicing issue, as I've been playing with the voicing for  a while and I tried the hottest settings for the pickups.
It did the same thing when I first got it.
I need some help here! We're using it all the time for my band, and I am afraid I am going to blow up an amp by using the ART tube mic preamp we use to heat up it's signal.
We have to turn it up full on a Fender Twin!

William Price

[Mark II]

make sure that the instrument cable you are using is ok.
verify the TWINS state by means of a guitar.

@rhodes
check the grey RCA cable and it's connection to the harp's output.
use an adaptor (RCA jack to 1/4' instrument jack) to hook the piano's harp right to the TWIN.

good luck
Mark II