Hi

Any suggestions why I'm unable to get Atmos soundtrack through my Denon 4500 AV?

* I get Dolby True HD soundtrack - not Atmos

* I'm using 4k discs with Atmos soundtrack

* Latest software version M36.R.0338

* UBP X800 (NOT M2 model)

* Digital Audio Output - Auto

* BD Audio MIX setting - Off

* Have performed factory resets 

* HDMI settings and lead all suitable

* I get Atmos through Netflix & iTunes movies from Apple TV so don't see this as an AV issue.

Am I missing something simple, or could this be a fault?

Any suggestions would be appreciated.

Many thanks