If the unit is behaving erratically but doesn't have a hardware failure, a factory reset (initialization) is often the first step recommended in the service documentation: the unit using the main power button.
is an essential roadmap for maintaining this 60-pound beast, which features massive power reserves and a complex multi-board architecture. Technical Specifications and Power Denon Avc-a1se Service Manual
Press the button once while continuing to hold the other two. If the unit is behaving erratically but doesn't