When first tested, the CD player did not function properly at all. As I have some familiarity with this product, having owned 2 Sony 5-changer CD players over the past 20 years, and based on communications with Sony support, I had to do some maintenance on the CD player to get it to work. When loading CDs, some would play, others no. Opened the unit, cleaned the laser, and other dusty areas. Got it working, but won't play some CDs that play on other Sony CD players I have owned.