my understanding from reading these posts in this forum is that I should be getting PCM for audio output.
right now everything (DD, DD+, DTS, Atmos etc…) is showing as audio output 5.1.2 ch Dolby Surround on my Onkyo RZ820 receiver.
My receiver is connected to my LG Oled TV via input 2 ARC and my Apple TV is set to Dolby Atmos which I am getting fine with Netflix and Apple Movies, saying that I am also getting output 5.1.2 ch Dolby Surround for any other audio other then Atmos so something does not make sense to me.
I could not find any settings on my receiver that set the default to Dolby Surround, saying that the culprit was the MOVIE/TV button - by selecting this I was able to switch to Dolby Digital. I am now getting DD for INFUSE, Netflix and Amazon ion my Apple TV. (or DD+ directly on my LGTV Netflix and Amazon apps - I was under the impression DD+ was available on Netflix Apple TV but that is not a deal breaker for me)
Strange that I am not getting PCM - but at least I am getting DD (see attached) … so I checked my Apple TV settings and my audio options are set as follows:
change format - OFF
immersive audio - Dolby Atmos ON.
I am OK with this setup on my ONKYO receiver unless I am missing something else. ( only minor nuisance is that now there is a lot more audio switching which creates a “click sound” on the receiver from the audio input changes).
If your source material is 5.1 Dolby Digital/DTS, then you aren’t really losing anything with your current setup.
If you are playing a lot of 7.1 TrueHD/DTS-HD MA files, then yes there would be a difference. Whether you notice this or not will greatly depend on the person, and the type of speakers being used. There are quite a few discussions on the web regarding this topic and the opinions range from ‘no difference’ to ‘night and day’…so YMMV.
just a quick update - I connected my Apple TV4K directly to my receiver and from what I can tell there still is no LCPM option, unless the Direct option is LCPM
Here are the audio options I have with INFUSE:
DTS: Neural X. — I am testing this compared to DD when my Apple TV 4 was connected directly to my TV
Dolby Surround TV Logic
All Channel Stereo