I am running my server from my pc on a gigabit Ethernet and via earc to my Denon 3800 H to the tv. when playing via plex player denon will not recognize atmos. whwn i use the same file on a usb denon will play atmos. whats wrong on my set up???
There are two types of Atmos for home theaters: TrueHD + Atmos, the type found on Blu-ray discs, and Dolby Digital Plus + Atmos, the type used by streaming services such as Netflix.
The Plex app on the Sony (or any TV) will not pass TrueHD audio. It will be transcoded to another format and the Atmos information lost. This is a TV manufacturer restriction.
The Plex app on the Sony will pass Dolby Digital Plus + Atmos.
If you want TrueHD + Atmos audio, acquire a Nvidia Shield Pro. It and the Xbox are the only off the shelf streaming devices that support TrueHD + Atmos passthrough (based on forum comments, the Shield seems to be preferred over the Xbox).
Rumor has it that the Amazon FireTV Cube v3 supports, or soon will support, TrueHD passthrough. However, I have not seen any confirmation of that (not that it doesn’t exist, I just haven’t seen it).