Multichannel audio incorrectly mapped

A fix for this is already in the making and I think I can say, that the issue itself will be fixed with that fix hopefully soon :wink: I hope, Iā€™m not going out on limb here writing this, @sam_nazarko?

Please try this:

Reverting to the old .conf file does fix the channel mapping problem, but it introduces other issues. Once in a while it will make the sound go completely haywire. The speakers will start crackling and generate loud noises. Once in this mode, the only way I have found to restore normal operation is to reboot.

Ah. We have one other tester with that issue. Have a look at @Marcianoā€™s posts in the link I sent you and see if itā€™s the same with you.

My Vero4k is outputting 2 channels only regardless of the audio settings I select. Weirdly though all 7.1 channels light up on my Pioneer AV receiver.
I am not that familiar with Putty (to use SSH) but is there any (simple) testing I can do as it it really impacting my movie viewing enjoyment. This is a shame as otherwise it is a stunning bit of kit.

I have tried selecting pass-through and my receiver will decode most audio itself so I am puzzled why the pass-through doesnā€™t just send out an unmodified audio stream for my receiver to decode.

I have also used the test files further up this thread and they all work incorrectly usually just as 2.1 audio.
Thanks

Have a look for accessing the commandline in the wiki. Try the reboot/escape method with a keyboard attached if you donā€™t want to use putty, but putty isnā€™t very complicated either - just pick SSH, enter the ip address of your vero and answer yes to the warning message about if you are sure you want to connect.

Then try the fix three posts above this one. It seems to work for 99% of people and should be in the November update at the end of the month, anyway.

Hi @Xanderzdad ā€” we should have it included in the next update as @grahamh has commented.

In the interim, I have another (simpler solution) for you.

Go to My OSMC -> Updates -> Manual Controls
Under Apply Hotfix, enter: [deprecated]
This will apply the solution that was proposed above and reboot your device.
Please then test your audio and let us know if the issue is resolved.

Sam

If pass-through is not working, check whether

Settings-> Player ā†’ Video ā†’ Sync playback to display

is disabled since it prevents pass-through if being activated. Perhaps this is the reason all is transcoded to LPCM which is wrongly mapped without the workaround/hotfix mentioned in this thread.

Thanks Sam

Iā€™ll try it out tomorrow and let you know.

Sadly it is disabled so that isnā€™t the problem. Thanks though.

#edited to clarify I meant the sync playback is disabled.

A debug log would help here.

I hope to get a chance to try it tonight and will read up on how to create and send you a debug log.

I am having the same issue as this with regard to the BL & BR mapping to SL & SR instead. From an audio (both music and film) point of view 5.1 should output to L C R BL BR & LFE whereas 7.1 would also add in SL & SR.

I am also witnessing this behaviour now I am trying out the fix.
On top of this I also lost the main speech (I guess mapped to the Centre channel) on nearly all the combos I tested. In the end I had to rig my AV to front focussed surround to get any speech back.
BTW I am only testing on movies as I have no 5.1 or 7.1 music files to hand.

If the source has channels L C R SL SR, they will be mapped to L C R SL SR even in a 7.1 system, where S=ā€˜sideā€™ or ā€˜surroundā€™. If the source has L C R BL BR they should be mapped to L C R BL BR. I canā€™t test as I donā€™t have a 7.1 system. This may not be what you want, but it is logical.

Once weā€™ve squashed the bugs, Iā€™m going to look at adding an option to upmix sides to sides and rears.

Can you check whether LFE and FC are reversed, and tell us what media does this, please?

The logic is correct and is applied in all scenarios. But I donā€™t believe FL+FR+C+BL+BR files exist. The back channels are 7.1 channels only.

Weā€™ve talked about this and have done extensive testing already at a different place here in the forum. Iā€™ve tested 5.1 PCM and bitstream format files as well as 7.1 PCM and bistream format files (audio and video) and the mapping of surround channels is always the same: 5.1 consists of FL+FR+C+SL+SR+LFE and BL+BR are added for 7.1: FL+FR+C+SL+SR+LFE+BL+BRā€¦
This is referring to what the Vero 4k outputs via HDMI AND what a 7.1 AVR/loudspeaker setup receives and plays back accordingly.

And what makes this easy to understand and why it probably wonā€™t be changed: This is the channel mapping given by DTS and Dolby (test videos show exactly this ā†’ adding back surround channels, NOT side surround channels when moving from 5.1 up to 7.1). :wink:

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I wasnā€™t aware of that convention so good to know.
It seems a little odd though since a 5.1 system would have the speakers behind traditionally (i.e. I think you would sit inside the ā€˜boxā€™ of the speakers). My 7.1 system is laid out as such with the extra 2 speakers being to the side and slightly in front of my listening position but in all honesty it doesnā€™t impact on my listening too much.

Yep, youā€™re completely right that it might be a bit stupid when playing 5.1 content without any upmixing enabled over a 7.1 system with side surround speakers (or even slightly front-side surround speakers like you describe yours)ā€¦ But thatā€™s what even the test videos by Dolby and DTS showing a simulated surround system imply.

The only problem here with a 7.1 system which is used with a Vero would be this now: as 5.1 channel PCM sources are passed to the receiver with two additional blank channels (8 channels are sent in total), no upmixing can be done by the AVR (like it can be done with bitstream format source files) to at least spread the audio of the side surround channels also to the back surround channels.

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OK I have found a major boob I made in my testing.:roll_eyes:
Once I activated ā€œKeep Audio Device Aliveā€ then all the crazy issues I was having with the update disappeared. I was tearing my hair out until then as the Centre was randomly disappearing.
I had disabled this setting as it generated white noise once I stopped playing but I have since narrowed that done to the ā€œSend low volume noiseā€ option.
Therefore please ignore some of my previous feedback as it appears (fingers crossed) to all be working.

I will keep testing but the only odd issue is that my AV still shows 7.1 speaker activation even if the source is stereo or 5.1, which suggests a signal of some kind is still going the the redundant channels.Occasionally the 5.1 shows correctly so I am not sure if the codec is being resampled or passing thorough clean.

This is from SWRobelā€™s latest log. Somehow Kodi thinks this mp4 wants two rear speakers.

18:51:42.962 T:3761239024   DEBUG: GetMusicVideoId (nfs://192.168.0.7/volume1/Downloads/Demo Material/Audio/ChID-BLITS-EBU-Narration.mp4), query = select idMVideo from musicvideo where idFile=36
18:51:42.994 T:4070568944    INFO: CActiveAESink::OpenSink - initialize sink
18:51:43.157 T:4110532608   DEBUG: ------ Window Init (Custom_Cache_Progress.xml) ------
18:51:43.158 T:4110532608   DEBUG: started alarm with name: iscachingtimer
18:51:43.356 T:4110532608   DEBUG: LIRC: Update - NEW at 4364855:160 0 KEY_OK_UP linux-input-layer (KEY_OK_UP)
18:51:43.365 T:4070568944   DEBUG: CActiveAESink::OpenSink - trying to open device ALSA:hdmi:CARD=AMLM8AUDIO,DEV=0
18:51:43.366 T:4070568944    INFO: CAESinkALSA::Initialize - Attempting to open device "@:CARD=AMLM8AUDIO,DEV=0"
18:51:43.369 T:4070568944    INFO: CAESinkALSA - Unable to open device "surround51:CARD=AMLM8AUDIO,DEV=0" for playback
18:51:43.369 T:4070568944    INFO: CAESinkALSA - Unable to open device "surround71:CARD=AMLM8AUDIO,DEV=0" for playback
18:51:43.371 T:4070568944    INFO: CAESinkALSA::Initialize - Opened device "sysdefault:CARD=AMLM8AUDIO"
18:51:43.372 T:4070568944    INFO: CAESinkALSA::InitializeHW - Your hardware does not support AE_FMT_FLOAT, trying other formats
18:51:43.372 T:4070568944    INFO: CAESinkALSA::InitializeHW - Using data format AE_FMT_S32NE
18:51:43.372 T:4070568944   DEBUG: CAESinkALSA::InitializeHW - Request: periodSize 2048, bufferSize 16384
18:51:43.396 T:4070568944   DEBUG: CAESinkALSA::InitializeHW - Got: periodSize 2048, bufferSize 16384
18:51:43.396 T:4070568944   DEBUG: CAESinkALSA::InitializeHW - Setting timeout to 372 ms
18:51:43.397 T:4070568944   DEBUG: CAESinkALSA::GetChannelLayout - Input Channel Count: 6 Output Channel Count: 8
18:51:43.397 T:4070568944   DEBUG: CAESinkALSA::GetChannelLayout - **Requested Layout: FL,FR,FC,LFE,BL,BR**
18:51:43.397 T:4070568944   DEBUG: CAESinkALSA::GetChannelLayout - Got Layout: FL,FR,LFE,FC,BL,BR,UNKNOWN1,UNKNOWN1 (ALSA: FL FR LFE FC RL RR NA NA)
18:51:43.397 T:4070568944   DEBUG: CActiveAESink::OpenSink - ALSA Initialized:
18:51:43.397 T:4070568944   DEBUG:   Output Device : AML-M8AUDIO
18:51:43.397 T:4070568944   DEBUG:   Sample Rate   : 44100
18:51:43.397 T:4070568944   DEBUG:   Sample Format : AE_FMT_S32NE
18:51:43.397 T:4070568944   DEBUG:   Channel Count : 8
18:51:43.397 T:4070568944   DEBUG:   Channel Layout: FL,FR,LFE,FC,BL,BR,UNKNOWN1,UNKNOWN1

BTW mediainfo reports Side: but what do they know?