Casio CZ/ VZ/ FZ - Pro Series

PS:

Is there any hiss coming out of the audio.  Try using the headphone 
output.  When you move the volume from 0% to 100% is there an 
increase in hiss? At 100% volume, does moving the chorus slider from 
0% to 100% increase the hiss?  (I just tested this with a spare pair 
of computer speakers, using a miniplug to 1/4" stereo adapter.)

If the answer to both is yes, there would seem to be some audio 
circuitry working.

Hope this helps.

Dr. Steve