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ledzep1
Headliner II
November 16, 2020

Dolby 5.1 content outputting as multichannel PCM 7.1 (since LPCM update)

Hi

Thought I would create this thread as a few have reported this issue in the lpcm update threads that are marked as solved so perhaps best to keep it separate.

Issue:

Before the LPCM update last week my sonos arc would receive atmos and Dolby digital 5.1 from the Apple tv 4k box, audio settings were set to the default AUTO-Atmos available.

My LG CX is capable of passing LPCM.

 

Now since the LPCM update with the above settings I still get atmos from apps such as netflix, apple tv + on the apple 4k box, but any content in dolby 5.1 is now outputting as multichannel PCM 7.1, 7.1 being the issue, it should be outputting as multichannel PCM 5.1

 

I have seen similar posts with this issue on the same device and other devices as well.

 

Thank you 

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    Rich76
    November 19, 2020

    Hi

    Thought I would create this thread as a few have reported this issue in the lpcm update threads that are marked as solved so perhaps best to keep it separate.

    Issue:

    Before the LPCM update last week my sonos arc would receive atmos and Dolby digital 5.1 from the Apple tv 4k box, audio settings were set to the default AUTO-Atmos available.

    My LG CX is capable of passing LPCM.

     

    Now since the LPCM update with the above settings I still get atmos from apps such as netflix, apple tv + on the apple 4k box, but any content in dolby 5.1 is now outputting as multichannel PCM 7.1, 7.1 being the issue, it should be outputting as multichannel PCM 5.1

     

    I have seen similar posts with this issue on the same device and other devices as well.

     

    Thank you 


    Hi

    I have an LG OLED B7 and since the update I can now get my OPPO 203 to play pcm 5.1 when a DTS disc is in use which is great. the volume was a lot lower than when Atmos is playing. however it means I don’t need another Blu ray player.

    I have the same issue with the Opposite 203 and my LG OLED C9. I now get 5.1 from DTS discs but the volume is so low it’s almost unwatchable. 

    Really disappointing as I only bought the Arc as I knew it would eventually work with DTS content with the LPCM update but the quality of the audio this way is terrible.

    n1c0
    Trending Lyricist I
    November 19, 2020

    @Ryan S are you guys looking into this issue? We’re glad the LPCM update is out but there are multiple reports of devices defaulting to sending 7.1 tracks to the Arc and the soundbar is unable to downmix it to 5.1. In most cases this causes missing dialogue or audio coming out from the wrong channels. On top of that the sound volume when using LPCM is really low compared to bitstream.

      John B
      November 19, 2020

      @Ryan S are you guys looking into this issue? We’re glad the LPCM update is out but there are multiple reports of devices defaulting to sending 7.1 tracks to the Arc and the soundbar is unable to downmix it to 5.1. In most cases this causes missing dialogue or audio coming out from the wrong channels. On top of that the sound volume when using LPCM is really low compared to bitstream.

      I could be wrong, but I think Sonos HT speakers just play what they are sent (or silence if sent something incompatible like DTS), and don’t attempt to do any downmixing or other audio processing.  

      I thought the demand for multichannel LPCM came from the gamers.  I am puzzled as to why there was an expectation this would deal with the DTS issue on Blu-rays.

      Is the volume low on LPCM for all scenarios?  I ask in genuine curiosity.

      n1c0
      Trending Lyricist I
      November 19, 2020

      @Ryan S are you guys looking into this issue? We’re glad the LPCM update is out but there are multiple reports of devices defaulting to sending 7.1 tracks to the Arc and the soundbar is unable to downmix it to 5.1. In most cases this causes missing dialogue or audio coming out from the wrong channels. On top of that the sound volume when using LPCM is really low compared to bitstream.

      I could be wrong, but I think Sonos HT speakers just play what they are sent (or silence if sent something incompatible like DTS), and don’t attempt to do any downmixing or other audio processing.  

      I thought the demand for multichannel LPCM came from the gamers.  I am puzzled as to why there was an expectation this would deal with the DTS issue on Blu-rays.

      Is the volume low on LPCM for all scenarios?  I ask in genuine curiosity.

      I get the low volume on PS5, Series X and Apple TV 4K. The latter is the most problematic one with the 7.1 issue  since there’s no way to force 5.1 through settings like the consoles can.

        ledzep1Author
        Headliner II
        November 19, 2020

        @Ryan S are you guys looking into this issue? We’re glad the LPCM update is out but there are multiple reports of devices defaulting to sending 7.1 tracks to the Arc and the soundbar is unable to downmix it to 5.1. In most cases this causes missing dialogue or audio coming out from the wrong channels. On top of that the sound volume when using LPCM is really low compared to bitstream.

        I could be wrong, but I think Sonos HT speakers just play what they are sent (or silence if sent something incompatible like DTS), and don’t attempt to do any downmixing or other audio processing.  

        I thought the demand for multichannel LPCM came from the gamers.  I am puzzled as to why there was an expectation this would deal with the DTS issue on Blu-rays.

        Is the volume low on LPCM for all scenarios?  I ask in genuine curiosity.

        Hi

        Well for me I got stereo from DTS blurays before the update, TV set to bitstream/passthrough and bluray player set to bitstream.

        Not quite sure why you think this LPCM update was just for the gamers, I’m much happier to get multichannel pcm than stereo 2.0, just be nice if it was outputting correctly and not in 7.1.

        Also all my content on my apple tv 4k box in dolby 5.1 is output as multichannel pcm 7.1.

        So i’m not sure where you are coming from.

          John B
          November 19, 2020

          So what happens if you set your TV to output DD5.1?

          ledzep1Author
          Headliner II
          November 19, 2020

          So what happens if you set your TV to DD5.1?

          I have not looked to try, I know there is an auto setting but then that stops me getting full fat atmos from my oppo203.

          John B
          November 19, 2020

          So what happens if you set your TV to DD5.1?

          I have not looked to try, I know there is an auto setting but then that stops me getting full fat atmos from my oppo203.

          Where I am coming from is that if you want a Sonos HT speaker to play DD5.1 you have to send it DD5.1.  Although id you want Atmos on the Arc it needs to be DD+

          ledzep1Author
          Headliner II
          November 19, 2020

          So what happens if you set your TV to DD5.1?

          I have not looked to try, I know there is an auto setting but then that stops me getting full fat atmos from my oppo203.

          Where I am coming from is that if you want a Sonos HT speaker to play DD5.1 you have to send it DD5.1.  Although id you want Atmos on the Arc it needs to be DD+

          I’m not worried about DD 5.1 I just would like it to output correctly so multichannel pcm 5.1 not 7.1.

          Yes streaming atmos is atmos DD+ but from my 203 I get Atmos (True HD)

            John B
            November 19, 2020

            ‘ I just would like it to output correctly’

            By ‘it’ do you mean the Arc and by ‘output’ do you mean play?

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