Back to 10.5.0 on my 4670X. THE AUDIO ISSUE REMAINS!. The Roku is set to Auto and shows the Denon AVR supports to DD+ & Atmos. Yet only 2 channel, PCM stereo comes across the HDMI.
2 Weeks and my surround system can only function by re-digitizing the audio and then converting it to an emulated surround.
I have a great solution for anyone with the problem at this point. I purchase a Chromecast with Google TV for $39. Plugged it in to another HDMI port and guess what...I now again can watch Disney+ and HBOMax with full Atmos & DD+ sound. Shame on you Roku!