If your trying to use Dolby Access App with a receiver, in short Dont.
1) It currently isn't supported by anything but the demos on the Dolby Access App.
(Anything you could play prior in Atmos, didn't need this app. It doesn't add any benefit at the moment).
But it does give you problems like your having now. When I had it, it was a song and dance to get it working.
Working fine, turn on TV, well shit. Have to restart computer twice. Works fine. Turn off TV, shit. Have to restart computer twice. Works.
Also sometimes sound is slow to initialize. I would... turn computer on, press sound up. Nothing. Sound Test... Nothing. Play Video file... first 4 seconds nothing... Whoop there is the sound.
Also it makes it look like every audio signal you has an Atmos signal, but it doesn't.
Medieval 2 Total war /w fake Atmos signal
The best part is, it reduces all your quality to 48khz, where without the App only Atmos sound is reduced, everything else can stay 192kHz
And I would have to do this regularly, regularly setup my speakers. Regularly setup my spatial.
And it gets you, nothing. (At the moment). Nothing supports it through the windows setup. The worse part is unninstalling wont enitrely fix your problems. In the end I had to format and reinstall. I'm on CU, my Atmos works fine and dandy, I just didn't install the Dolby Acces App this time. Even the built in Windows "Movies & TV" app works fine with atmos, yet doesn't support the Atmos for home theater spatial settings.
There's my take. Format your drive, don't install it.
Battlefield 1, Battlefront, Test Tones, The video on the dolby homepage, Atmos movies, demo videos, they all work without the Dolby Access App.
Actually the atmos homepage video gives me dolby digital + ... Atmos Homepage Video (Picture)