F3 error on Proceed CDP display

Dear all,

I've bought a Proceed CDP and today I tested it for the first time. I live in Italy (230V AC, 50Hz), and my unit comes from US (110V); unit is setted to operate at 120V (110 doesn't exist). I've bought also an AC transformer to convert 230V to 110V. When I connect my Proceed CDP to external transformer initially unit turns on, but immediately after a strange message "F3" appears on display and unit becomes like dead: nothing functions, buttons, display...nothing!. Please help me! thanks in advance, ciao. Massimo