[kevwag]

Set PCM Settings to Stereo 2.0
Enable AC3 capable receiver
Enable AC3 Transcoding

Try this combination. Your TV should get Dolby for multi channel and should pass that.

I just wanted to chime in and say thanks for posting this fix. I had the same problem and I've spent ***king days trying to sort it out!
I had tried every conceivable combination of settings to no avail, the ONLY thing I didn't try was setting the output to stereo, it's not just the last thing I'd try, it's something I would NEVER have tried! It's so illogical and counter-intuitive telling the software you have fewer speakers when you're actually trying to get it to work with more!

This whole fiasco has inspired me to hate the people at Dolby and wish bad things upon them. It's 2021 ffs, we should be able to get six simple channels of audio without all the nonsense of encoding multiple channels on top of each other, then calling it the opposite to what it actually is. They were putting four chammels of quadraphonic audio on a vinyl record in the late 1950s & early 1960s and assuming you could afford the equipment, all you had to do was plug it in and it worked straight out of the box. You didn't need to hide two of the speakers to make it work!