Latest Apple TV 4K firmware and Windows 10 PMS as of 2/26/2020.
Why does PMS only convert 7.1 Dolby TruHD to only 5.1 PCM? I thought it would convert it to 7.1 PCM.
Bumppp
It should convert to 7.1 lossless FLAC.
What are your Apple TV audio settings?
What is the Apple TV connected to (AV/R or TV)?
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Apple TV 4K is connected to Denon AVR-4400h. Settings in Apple TV are the highest audio settings I believe with Atmos selected. There really is not much to set in the way of audio settings in the Apple TV. I don’t see any way to specify the number of channels your receiver has in Settings. The Plex app has even less settings. You can pick the audio stream in the Plex app. I pick the Dolby TruHd stream and it has 8 channels but as I said earlier, PMS only sends 5 channels to the Denon 4400.
can you post a screenshot of your pms dashboard while playing this problem video?
something like
If it’s a full transcode, you’ll get OPUS. If it’s just the audio being transcoded, you should get FLAC.
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See attached screenshots and thx.
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Plex says eac3 which is Dolby digital, the receiver seems to indicate pcm multi channel (not dd).
I thought eac3 is enhanced Ac3 thus 8 channels vs. 6 for standard ac3. And the Apple TV won’t take EAC3 anyways.
The AppleTV will not output EAC3. It will decode it and output it as LPCM. This is true even for Lossy Dolby Atmos from Netflix and the likes. The question here is are we sure the AppleTV 4K is actually receiving EAC3 7.1 (Dolby Digital Plus 7.1) from PMS. Do you happen to have Tautulli? It provides more details info about the transcode.
FYI-The enhanced player (which is required for PMS to transcode to FLAC) is gated behind Plex Pass.
That is quite interesting. PMS is transcoding the TrueHD 7.1 to Dolby Digital Plus 7.1. The AppleTV should be decoding that Dolby Digital Plus 7.1 to LPCM 7.1 and sending that out to the AVR-4400H but its not. Can you drill down further into the AppleTV 4K’s Audio Format settings and provide that screenshot?
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I was able to reproduce the issue with the native AppleTV player. Using the enhanced player, the AVR received LPCM 7.1
CC: @DaveBinM @sergiou87
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SInce @acribb is not a PP user, he won’t get OPUS on a transcode.
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I was not able to fix the issue by turning Atmos off.
See attached evidence.
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@acribb Unfortunately as a non Plex Pass user it will not do LPCM 7.1 as of now. I let the dev know already.
Do we have an eta on when this will be fixed since it sounds like this is a bug for non Plex pass users? Is PMS sending a 7.1 audio stream and the issue is that Plex Player on the Apple TV 4K is not properly decoding it to 8 channels?
No idea on ETA.
Any updates from the devs on when this can be fixed?
Also, when the Dolby TruHD or DTS HD-MA track is converted by Plex into an EAC3 container, is the audio losing any bitrate and is being down sampled or is the same lossless audio being repackaged in a different container compatible with Apple TV 4K?
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