WHEN I ON MY HI

Question

WHEN I ON MY HI FI SYSTEM THERE IS NO SOUND COMING OUT OF THE SPRAKERS, AND WHEN I INCRESE THE THE VOLUME TO 16 OR ABOVE THE HIFI SYSTEM AUTIMATICALLY TURNS OFF. TO RE START THE SYSTEM YOU HAVE TO TURN IT OFF FROM THE MAINS FIRST. THE MODEL NUMBER IS SONY HCD-WZ5 AND THE SERIAL NUMBER IS 6613423.