Yes, because LG FAQd up the gamma on B8 and never fixed it.
Do you have the same problem when using the Netflix TV App, i.e unable to send Atmos to your AVR? I had the same problem initially but had to alter something within the sound settings on the B8.Just tested it on Onward on the Disney app.
When using the internal speaker with Atmos enabled, the top right tag shows both Atmos and Vision.
When set back to HDMI arc sound to the amplifier the Atmos tag no longer shows. The amplifier displays Digital+, I have a Denon X3400H. I have never managed to see Atmos on the Denon using the inbuilt apps. It will show when connected to the Xbox one on Netflix.
Is Atmos setting greyed out (in TV settings) and in off or on position? I doubt it will be a cable issue. I assume you have the top tier Netflix package?Thanks for the responses. Yes, I've tried Netflix, no Atmos from there either. Simplink is on, HDMI is set to arc and auto. Tried turning on to internal speakers and back to get the Atmos option to show but no, still Dolby digital+ on the receiver. Could it be the HDMI cable in use?