For anyone interested in using the denon binding with the newer Denon models where the HTTP interface is “disabled” (read: giving 403 Forbidden responses) I created a fork which seems to work (tested with the Denon X4400H)
The thing is that the denon binding support receiving events via telnet but always sends command via http no matter what the update option is set to. I rewrote the “send command” part in such a way that telnet is used for sending commands, too.
Note that this is not supporting all the HEOS stuff (there is another binding which does and the too can and do work together).
I’m mainly still using the Denon binding because of a shortcoming of the HEOS implementation when it comes to AVRs with multiple zones: they can’t be switched on/off seperately and the volume of the zones is summed up (well, eeerr… yes) instead of being reported seperately. This can’t be came by by the HEOS binding, since it’s already messed up in the protocol (at least this is the way my AVR is behaving).