This unit is amazing and working %100. One problem it has is that the door for the front inputs doesn't close all the way besides that this is perfect working order. the only difference between this and the newer version is the upgrade to 8k besides that its the exact same model. The Marantz AV7705 11.2 Channel 4K Ultra HD AV Surround Pre-Amplifier is a high-quality home theatre receiver designed for immersive surround sound experience. With various audio inputs such as Digital Coaxial RCA, USB, HDMI, and more, this amplifier offers compatibility with