2007 CEDAR CREEK TRAILER Electrical System Problems

THIS IS IN REFERENCE TO A CONCERTONE 5.1 DOLBY SURROUND SYSTEM MODEL ZX600 INSTALLED IN MY 2007 CEDAR CREEK SILVERBACK TRAVEL TRAILER MANUFACTURED BY FOREST RIVER INC. I PURCHASED THIS NEW TRAVEL TRAILER IN MARCH 2007 FROM TOM JOHNSON CAMPING IN CONCORD, NC. INCLUDED AS A $360 OPTION WAS THE SUBJECT CONCERTONE UNIT. SINCE PURCHASING THIS CAMPER, THE CONCERTONE UNIT HAS BEEN REPLACED FOUR TIMES BY TOM JOHNSON CAMPING, BECAUSE THESE UNITS FAILED TO OPERATE AFTER 6-9 MONTHS. THE CURRENT UNIT IN MY TRAVEL TRAILER WAS REPLACED BY TOM JOHNSON EARLIER THIS YEAR. CONCERTONE HAS A ONE YEAR WARRANTY. THE CURRENT UNIT IS DEFECTIVE AND WILL NOT OPERATE. AFTER BEING IN THE RADIO FUNCTION FOR ABOUT FIVE MINUTES, IT ERRATICALLY AND LOUDLY MOVES BETWEEN THE RADIO FUNCTION AND LOAD A DISK, AND THE LIGHTS ON ITS DASHBOARD FLASHES ON AND OFF. WHEN I TRY TO SHUT THE UNIT OFF, IT...