Transcoding Surround speaker issue in 2.2.0

[brians]

I notice that the audio output on my Sonos system is not correct now. Since the Sonos Playbar does not support DTS I had set in System Settings:
Number of Channels 5.1
Enable passthrough - not checked (I could leave checked to pass DD, but found a couple 2.0 streams that were incompatible with no sound at all so I found it easier to leave unchecked and have everything re-encoded - now thinking, it didn't seem to pass DD 5.1 before so maybe that is why I had set that way).

In the previous version this worked perfect and always output a DD 5.1 signal which converted DTS in realtime. The stereo and centre channels sounded correct to me.

Now with the new update, the center channel (eg. dialog) seems to come out the left side.

This also happens on other multi-channel audio other than DTS... centre channel/dialog are heard more on the left.

Seems that the channels got mixed up somehow when transcoding surround.

As a workaround for now I enable pass through and uncheck DTS capable receiver... then make sure I set the channels at 2.1 (even 3.1 causes issue with coming out left side). Now DD 5.1 streams are passed through and anything else gets converted to 2.1.

Please look into fixing this in future release, thank you.

Brian

[davilla]

odd, so many areas in play. need info on.

1) ATV4 audio settings.
2) MrMC audio settings.
3) MrMC.log with debug enabled.
4) Sonos Playbar setting (if any) and what it is capable of doing.

MrMC v2.1.0 had a channel mapping issue with audio. MrMC v2.2.0 corrected that.

[budtz80]

I have the same problems. Channel mapping seems off, at least for DTS tracks. If i set mrmc to 2 channels i get PLII. Set it to 3 and i get Dolby digital but with voices in the side Channel. Set it to 5.1 and i get voices in the surround left Channel. It works however for Dolby 5.1 tracks. The issues i get is with DTS tracks. Setting mrmc to passtrough DTS gets me correct DTS sound but after closing the video file i get no audio or ui sounds at all on the Apple tv in any apps. So this is not an option. Playing a dd5.1 file in Netflix gets audio back. I think its the switch from dts back to PLII that dosnt work somehow. I have tried lots of settings but with same resaults.

Something is very wrong with mrmc and/or the Apple tv with theese things

[amet]

Let's get you into TestFlight, email [email protected] with your Apple ID email

Sorry for the issues, we will get to the bottom of it

[MrTalus]

I am also having the same issue with the center channel being played in the left surround speaker.

This happens when I go HDMI to my Samsung TV and then Optical Dolby Digital Format to my Sony receiver.

When I go HDMI straight into my Sony receiver in PCM format, I only hear surround channels and no subwoofer, front, left, or center channels at all. I should add that the surround left and right channels are in fact coming from my front left and right speakers.

[timstephens24]

There's something still a little wrong with the mappings, but they're a lot better now. Here's my mappings (note: BOLD denotes wrong mapping)

DTS-HD MA (5.1) with Passthrough (played as DTS 5.1)
Left Speaker ---> Left Speaker
Center Speaker ---> Center Speaker
Right Speaker ---> Right Speaker
Right Surround ---> Right Surround
Left Surround ---> Left Surround
LFE ---> LFE

DTS-HD MA (5.1) w/o Passthrough (played as PCM 5.1)
Left Speaker ---> Left Speaker
Center Speaker ---> Center Speaker
Right Speaker ---> Right Speaker
Right Surround ---> Right Surround
Left Surround ---> Left Surround
LFE ---> LFE

Dolby TrueHD (7.1) w/ Passthrough (played as PCM 7.1)
Left Speaker ---> Left Speaker
Center Speaker ---> Center Speaker
Right Speaker ---> Right Speaker
Right Surround ---> Right Rear Surround
Right Rear Surround ---> Right Surround
Left Surround ---> Left Read Surround
Left Rear Surround ---> Left Surround
LFE ---> LFE

Dolby TrueHD (7.1) w/o Passthrough (played as PCM 7.1)
Left Speaker ---> Left Speaker
Center Speaker ---> Center Speaker
Right Speaker ---> Right Speaker
Right Surround ---> Right Rear Surround
Right Rear Surround ---> Right Surround
Left Surround ---> Left Read Surround
Left Rear Surround ---> Left Surround
LFE ---> LFE

DTS-HD MA (7.1) with Passthrough (played as DTS 5.1)
Left Speaker ---> Left Speaker
Center Speaker ---> Center Speaker
Right Speaker ---> Right Speaker
Right Surround ---> Right Surround
Left Surround ---> Left Surround
LFE ---> LFE

DTS-HD MA (7.1) w/o Passthrough (played as PCM 7.1)
Left Speaker ---> Left Speaker
Center Speaker ---> Center Speaker
Right Speaker ---> Right Speaker
Right Rear Speaker ---> Right Surround
Right Surround ---> Right Rear Surround
Left Surround ---> Left Rear Surround
Left Rear Speaker ---> Left Surround
LFE ---> LFE

Dolby AC3 (5.1) w/o Passthrough (played as PCM 5.1)
Left Speaker ---> Left Speaker
Center Speaker ---> Center Speaker
Right Speaker ---> Right Speaker
Right Surround ---> Right Surround
Left Surround ---> Left Surround
LFE ---> LFE

Dolby AC3 (5.1) w/ Passthrough (played as Dolby 5.1)
Left Speaker ---> Left Speaker
Center Speaker ---> Center Speaker
Right Speaker ---> Right Speaker
Right Surround ---> Right Surround
Left Surround ---> Left Surround
LFE ---> LFE

[davilla]

A testflight to check the both channel mapping issues will get pushed up tomorrow.

[timstephens24]

So I guess the next question: is MrMC using a similar method as say the RPi2/3 and passing DTS-MA and TrueHD as lossless PCM now like the since I'm actually getting all 7 channels?

[davilla]

Passing DTS-MA and TrueHD as lossless PCM is the only way it will work on the AppleTV4 until Apple provides a real passthrough API.

[timstephens24]

I figured as much, but lossless PCM is just as good except in a few instances. I would like Atmos since I have a 7.2/5.2.4 setup, but I'm not holding my breath with the ATV4.