Hi Kevin and welcome to JustAnswer,Thank you for the question and your patience. Should you still need assistance for information purposes only...Initially, bear with us; re-confirm and post back with the complete model number of the Marantz.
Appreciate the information.
Have you tried a RESET?
Consider a RESET.
A reset is both a test and a try of a fix. As it implies, a reset would force the unit to revert back to factory defaults removing glitches and config errors but would include memories, presets and user preferences. After a reset, the initial setup would have to be performed. If have not been done and should you venture to try: Please click HERE.
May have to be done a number of times.
This is very critical - a reset however would not be corrective of an internal hardware concern; but it would be confirmed. In some instances, it may even expose/cause other issues.
Please post back results / observations of the above once tried.