Rhodes Chroma Polaris

Hi all,
Recently acquired a Polaris.  To my dismay when I switched it on, not working!  The LEDs 
light up (dont blink just light up) and when I turn it off and on again different LEDs light 
up, sometimes many, sometimes few. Nothing seems to respond, not even midi. Very 
strange.  I read somewhere this could be a problem with the power supply being dirty, or  
a much more serious problem with the unit.  Please help.

An angry shopper,
Marco