Hi Mark

My guess is the system Controller in the downstairs system is the 518 and not the 565V. As the 518's would appear to be set for resolution enhancement, rather than as a digital pre-amp, this would explain why the parmater values change rahter than Volume.

Switch the system off and press "Clear" and the various components will identify their status as Controller or Non-Controller.

My system Controller setting seems to work OK with all units set to Auto - the Left 5K taking the Controller role. It may well be that manually setting up the required Controller and Non-Controller parameter on each of your units will remove the problem.

Mr Meridian is the Comms guru however and he may well have another solution!

Regards

Mark

(Just how many Marks are there on this forum!)

System 1:
568.2MM, G98DH, Denon DVD-A1XV, Sony CDP-228ES, UHD722, D5KC, D5500.2K, DSP33, Sony UDP-800, AppleTV 4K, Sony KE85XH9096BU

System 2:
562V, M20, AppleTV

System 3
501, 555, AppleTV, Acoustic Energy AE1