I have MC26 audio set to marantz-AVR (NVIDIA High Definition Audio)[Direct Sound] and Bitstreaming: Yes (HDMI). Windows speaker setup is Dolby Atmos for Home Theater. My understanding is that this is the correct configuration to pass Dolby-TrueHD (with Atmos) over HDMI to my Marant AV7705 to get Dolby Atmos. Instead, it plays in Dolby Audio - Dolby Surround with the height speakers sent to the front and backs instead of the four ceiling speakers in my 7.2.4 setup. I also tried using the [WASAPI] device option, but that made no difference.
I'm using a Dolby Atmos 7.1.4 Test.mkv to troubleshoot this issue. The Marantz will not output Atmos correctly with MC. However, if I open/play this file back using Windows Media Player, it works fine and my Marantz shows Dolby Atmos, playing in 7.1.4 using the ceiling speakers as expected.
What is JRiver MC26 doing differently with Bitstreaming out this file?
EDIT: GotG trailer in the Dolby Access app works in Atmos fine too. Something configured wrong in JR MC26 and can't figure it out?