Exactly the same issue this guy had, posted in this forum back in 2020 on his denon unit
@STU-C hi mate, will not physically let me toggle it on/off next time I try to update as a test I’ll try disabling bluetooth to see what happens, but as it stands at the moment it all works so I’m hesitant, don’t need/use Bluetooth anyway but any additional fixes are always welcome hence why I’d like to get it sorted & updated.
Found another video of someone else having the same issue from 2021, again posted in this forum.
This is definitely a strange bug across multiple units at various os updates.