I'm unable to get sound thru my amplifier when I use the netflix app on my Samsung smart TV. I must change the setting on the TV to TV speaker to get any sound. The setup I have is a Samsung smart tv 65" with a Definitive Technology Mythos sound bar. The soundbar is discrete 5 channel wired to a Yamaha HTR-4065, direct TV, and blueray player are plugged into the reciever and the reciever is HDMI'd to the smart TV. Thereis no way to add additiona; wiring as the wiring is in wall 10 feet away.
I have the same problem with the same amplifer but on the Panasonic TX49FX700B using HDMI via the audio return channel.
There are some audio encoding formats that the HTR-4065 can't play. We found this out when we tried playing a Lord of the Rings DVD through it. Can you get the TV to send unencoded sound to the AV player? Also make sure the AV unit has the latest firmware update.