If you change inputs to something other than the network input, you may experience different results as when you're in t — Staff replied: “Denon does not default to port 80, so at this point we're going to recommend you contact support so they can diagnose what's going on.”
If you change inputs to something other than the network input, you may experience different results as when you're in that input, the directional pad defaults are overridden to use Denon's input specific codes for the input.
Another path is to edit your Remote Design to use different cursor commands. You'll see several in the Denon command set. The main set is simply "CURSOR UP" and so on. That's the one used for menus and system functions. You could add buttons specifically for those commands, or edit the directional pad itself to override.