If I am reading the docs site right, does this mean that since the Mac (with an HDMI port) can decode DTS-HD MA and TrueHD and send via PCM that I don’t need a Windows box in the living room anymore? If so, what is the best way to confirm it is working considering my receiver won’t be showing the logos anymore?
If you get 7.1 channels on the receiver it’s decoding the HD track
You can indeed play 7.1 DTS-HD MA and TrueHD on a mac if you use PCM. You need to connect a 7.1 PCM capable receiver via HDMI.
Note that you still can’t passthrough compressed DTS-HD on the mac due to OS restrictions (apparently).
I have disabled Dolby Digital and DTS in PMP audio settings and set the speaker config to 5.1, I’m using HDMI.
My receiver shows “PCM 4/3” when playing back a HD audio movie (I only have a 5.1 setup though).
Does this mean that it’s working correctly?
I looks like it works. So technically your mac plays HD audio, it just cant pass it on to the receiver via bitstream, thus the encoding needs to be done in the software. This gives you a lot of extras like getting the 24p ‘bug’ (as in Apple doesn’t care) out of the way by speeding up the audio slightly. Having said that, when using PCM the sound sounded different compared to bitstream. It might be me or my receiver, I have to look into it.
The most annoying part is lipsync.
Bitstream: Sync is great
PCM: Out of sync. I’m not at home right know, I don’t remember if the audio is early or late. But it is definitely out of sync.
OK, I will play around with it and see what I come up with. Exciting! I have been waiting for the day I can remove the last Windows machine from my setup.
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@Glennos said:
The most annoying part is lipsync.Bitstream: Sync is great
PCM: Out of sync. I’m not at home right know, I don’t remember if the audio is early or late. But it is definitely out of sync.
Set the audio delay number in the plexmediaplayer.conf and never look back 
@atrus said:
Set the audio delay number in the plexmediaplayer.conf and never look back
I’ll give it a go, but I can’t do it while watching something like you can with many other players. (yes, this is a feature request )
@Glennos said:
I’ll give it a go, but I can’t do it while watching something like you can with many other players. (yes, this is a feature request
Yes you can. By using a keyboard or a remote. For the remote you just need to assign a key to it
If you are talking about general audio delay (a number that all movies seems to have), then yes I agree. That should be in settings instead of the plexmediaplayer.conf. But that wouldn’t help your use case either because you can’t change stuff in Settings while playing a movie
Is there any way in PMP to at least check the bitrate on the audio track being sent by the app?
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Alright, here are my findings so far, w/ my output set to HDMI (of course), and 7.1 channels:
DTS
DTS-MA 7.1 soundtrack (Jurassic World) w/ DTS checked – core DTS is passed in bitstream
DTS-MA 7.1 soundtrack (same) w/ DTS unchecked – 7.1 PCM is passed
DTS 5.1 core only soundtrack (3 Days to Kill) w/ DTS unchecked – 7.1 PCM is passed
PCM soundtracks (not a lot of these in the world these days)
PCM 7.1 soundtrack (3:10 to Yuma) – 7.1 PCM is passed (this was also the case w/ PHT, though sometimes PHT would only output 5.1 LPCM)
So far, everything makes sense.
But the 1st finding below is a little weird.
Dolby
TrueHD 5.1 soundtrack (30 Days of Night) w/ Dolby checked – 7.1 PCM is passed
TrueHD 5.1 soundtrack (same) w/ Dolby unchecked – 7.1 PCM is passed
AC3 5.1 soundtrack (8MM) w/ Dolby checked – 5.1 DD is passed in bitstream
AC3 5.1 soundtrack (same) w/ Dolby unchecked – 7.1 PCM is passed
Now for the ultimate tests of possible PMP confusion:
DTS-HR 6.1 soundtrack AND AC3 5.1 soundtrack on the same movie (American Psycho) w/ DTS unchecked and DD checked – 7.1 PCM is passed (so it’s selecting the DTS soundtrack, presumably)
PCM 5.1 soundtrack AND AC3 5.1 soundtrack (Apocalypto, A Few Good Men) w/ DTS unchecked and DD checked – 7.1 PCM passed
So, overall, after looking at as many permutations as possible (and pretty much being forced to assume that the PCM tracks being passed w/ DTS-Ma tracks ARE in fact PCM versions of the DTS-MA track), it appears that the best way to do it is to leave DTS unchecked and leave DD checked. In all scenarios I’ve checked, it appears that PMP will pass the higher bitrate codec. Unchecking DD will certainly allow you to pass DD unencoded (and probably TrueHD as well), but this means that your computer will be doing the 5.1-to-7.1 conversion on its own, and I’d personally prefer to have my pre-pro doing that conversion. Now, obviously this recommendation means that your computer, rather than your receiver, would still be doing the 5.1-to-7.1 conversion on any core DTS soundtracks you have, but I’ll take that tradeoff in order to allow my DTS-MA tracks to be output to my theater.
And it APPEARS as if, if you have a TrueHD soundtrack and leave DD checked, it passes TrueHD unencoded, while magically passing movies w/ lone AC3 DD tracks in bitstream!!
In short, awesome job, guys!!
That being said, my skeptical self would love to see the bitrate of what’s being sent to my pre-pro so I can be sure…
Use the debug overlay screen during playback (Ctrl-Shift-D by default. oops-edit: Cmd-Shift-D for Mac, I think). You should see audio bitrate exceeding 1509 kbps (standard DTS) when playing DTS-HD MA.
@tobiashieta said:
If you get 7.1 channels on the receiver it’s decoding the HD track
From my experience, this isn’t necessarily an accurate characterization of how to interpret the 7.1 channel input reading on your receiver/pre-pro.
For example, when web trailers play before my movies, my pre-pro is seeing 7.1 Multichannel PCM just the same way it sees 7.1 PCM for other movie audio formats that are not checked, be they Mono, AAC stereo, MP3 or other.
In fact, thus far, it seems that you will pretty much see 7.1 PCM being sent from your computer to your receiver for everything that isn’t a checked format.
@Mediaconoclast said:
Use the debug overlay screen during playback (Ctrl-Shift-Dby default. oops-edit:Cmd-Shift-Dfor Mac, I think). You should see audio bitrate exceeding 1509 kbps (standard DTS) when playing DTS-HD MA.
Will give it a try. Thanks!
Alright, looks like my assumptions as to what it was passing were correct. Thanks again Mediaconoclast! Still having an ‘info’ option is quite the relief!
Awesome! I confirmed that leaving DTS unchecked will allow PMP on Mac platforms to decode DTS-MA 7.1 and send to a receiver as a full bandwidth PCM. Audio bitrates are consistently between 2800kbps and 3600kbps (which we all know is DTS-MA range, as core DTS is limited just above 1500 kbps) on the video I used to test, again using Cmd-Shift-D to check during playback.
This is great stuff Plex Team!
I saw the same thing (DTS-HD MA working at high bitrate and video at 1080p), though I tried to play a TrueHD Blu-ray and it didn’t work (showed dolby digital) and also said it was only sending me 720p. Then I went back to the original DTS-HD MA video and now it is showing low[er] bitrate AAC and 720p, also
FYI, the Mac version of Plex Media Player not longer can play DTS-HD MA. It got removed because of licensing
Wow. So that kills my plan to start using Plex on the new 2018 Mini for 4K playback. I have been using Kodi embedded on an older Mac Mini for the last few years, but that hardware can’t do 4K.
Is there an embedded Linux version of Plex Player that will run on Mac Mini x86 hardware and do pass-through of the latest audio standards?
TrueHD works but not DTS-HD MA for licensing reasons. I used MakeMKV to convert all my DTS-HD MA to audio tracks to FLAC. Aside from the initial work it has been great. Here is a script that does it (read all the comments, use at your own risk) hdAudioToFlac.sh.zip (2.0 KB)
