[RPi4][LE9.95.3] 7.1 input audio is sent out as 6.1

AMoo-Miki · May 30, 2021 at 1:15 AM

Content using a 7.1 configuration for the audio, with any of AAC LC, FLAC, or Vorbis codecs, play as 6.1 with the Lw and Rw channels being sent out as Cw. However, content using the 7.1 configuration with DTS XLL (DTS-HD) or MLP FBA 16-ch (TrueHD) put out all the 8 channels. I have tried with at least 20 AAC LC videos but have only one DTS-HD and one TrueHD.

All the AAC and FLAC encoded video files show the 8 channels on the "Player Process Info" dialog. These play with all the 8 channels on the current non-beta releases. Is there something I need to do to get full 8 channels out of AAC LC, FLAC, or Vorbis content?

Extras:

* Could the UNKNOWN1 be causing a problem?

* I have a 9.1 setup but ALSA sees the Marantz receiver as having 8.1 channels. Moreover, I just have one center channel which is FC; everything else is either left or right. Is this channel mapping something I can modify or influence?

Code

Enumerated ALSA devices:
    Device 1
        m_deviceName      : default
        m_displayName     : Default Audio Device ()
        m_displayNameExtra:
        m_deviceType      : AE_DEVTYPE_PCM
        m_channels        : FL, FR, LFE, UNKNOWN1, FC, BC, BL, BR, BLOC, BROC, FLOC, FROC
        m_sampleRates     : 32000,44100,48000,88200,96000,176400,192000
        m_dataFormats     : AE_FMT_S24NE3,AE_FMT_S24NE4,AE_FMT_S32NE,AE_FMT_S16NE,AE_FMT_S16LE,AE_FMT_S16BE
        m_streamTypes     : No passthrough capabilities
    Device 2
        m_deviceName      : sysdefault
        m_displayName     : vc4-hdmi-0 ()
        m_displayNameExtra: MAI PCM vc4-hdmi-hifi-0
        m_deviceType      : AE_DEVTYPE_PCM
        m_channels        : FL, FR, LFE, UNKNOWN1, FC, BC, BL, BR, BLOC, BROC, FLOC, FROC
        m_sampleRates     : 32000,44100,48000,88200,96000,176400,192000
        m_dataFormats     : AE_FMT_S24NE3,AE_FMT_S24NE4,AE_FMT_S32NE,AE_FMT_S16NE,AE_FMT_S16LE,AE_FMT_S16BE
        m_streamTypes     : No passthrough capabilities
    Device 3
        m_deviceName      : sysdefault:CARD=vc4hdmi0
        m_displayName     : vc4-hdmi-0 (vc4hdmi0)
        m_displayNameExtra: MAI PCM vc4-hdmi-hifi-0
        m_deviceType      : AE_DEVTYPE_PCM
        m_channels        : FL, FR, LFE, UNKNOWN1, FC, BC, BL, BR, BLOC, BROC, FLOC, FROC
        m_sampleRates     : 32000,44100,48000,88200,96000,176400,192000
        m_dataFormats     : AE_FMT_S24NE3,AE_FMT_S24NE4,AE_FMT_S32NE,AE_FMT_S16NE,AE_FMT_S16LE,AE_FMT_S16BE
        m_streamTypes     : No passthrough capabilities
    Device 4
        m_deviceName      : hdmi:CARD=vc4hdmi0,DEV=0
        m_displayName     : vc4-hdmi-0 (vc4hdmi0)
        m_displayNameExtra: MJI marantz-AVR on HDMI
        m_deviceType      : AE_DEVTYPE_HDMI
        m_channels        : FL, FR, LFE, FC, BL, BR, BC, BLOC, BROC
        m_sampleRates     : 32000,44100,48000,88200,96000,176400,192000
        m_dataFormats     : AE_FMT_RAW,AE_FMT_S24NE3,AE_FMT_S24NE4,AE_FMT_S32NE,AE_FMT_S16NE,AE_FMT_S16LE,AE_FMT_S16BE,AE_FMT_U8,AE_FMT_RAW
        m_streamTypes     : STREAM_TYPE_AC3,STREAM_TYPE_DTSHD,STREAM_TYPE_DTSHD_MA,STREAM_TYPE_DTSHD_CORE,STREAM_TYPE_DTS_1024,STREAM_TYPE_DTS_2048,STREAM_TYPE_DTS_512,STREAM_TYPE_EAC3,STREAM_TYPE_TRUEHD

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Playing AAC LC content:

Code

CAESinkALSA::Initialize - Opened device "hdmi:CARD=vc4hdmi0,DEV=0,AES0=0x04,AES1=0x82,AES2=0x00,AES3=0x02"
CAESinkALSA::InitializeHW - Your hardware does not support AE_FMT_FLOAT, trying other formats
CAESinkALSA::InitializeHW - Using data format AE_FMT_S24NE3

CAESinkALSA::GetChannelLayout - Input Channel Count: 8 Output Channel Count: 8
CAESinkALSA::GetChannelLayout - Requested Layout: FL, FR, FC, LFE, BL, BR, SL, SR
CAESinkALSA::GetChannelLayout - Got Layout: FL, FR, LFE, FC, BL, BR, BC, UNKNOWN1 (ALSA: FL FR LFE FC RL RR RC NA)

Playing DTS-HD content:

Code

CAESinkALSA::Initialize - Opened device "hdmi:CARD=vc4hdmi0,DEV=0,AES0=0x06,AES1=0x82,AES2=0x00,AES3=0x09"
CAESinkALSA::GetChannelLayout - Input Channel Count: 8 Output Channel Count: 8
CAESinkALSA::GetChannelLayout - Requested Layout: RAW, RAW, RAW, RAW, RAW, RAW, RAW, RAW
CAESinkALSA::GetChannelLayout - Got Layout: RAW, RAW, RAW, RAW, RAW, RAW, RAW, RAW (ALSA: none)

The full log for LE9.95.3 is here.

With LE9.2.6 which plays the audio correctly:

Code

Enumerated PI devices:
    Device 1
        m_deviceName      : HDMI
        m_displayName     : HDMI
        m_displayNameExtra:
        m_deviceType      : AE_DEVTYPE_HDMI
        m_channels        : FL, FR
        m_sampleRates     : 8000,11025,16000,22050,24000,32000,44100,48000,88200,96000,176400,192000
        m_dataFormats     : AE_FMT_FLOAT,AE_FMT_S32NE,AE_FMT_S16NE,AE_FMT_S32LE,AE_FMT_S16LE,AE_FMT_FLOATP,AE_FMT_S32NEP,AE_FMT_S16NEP,AE_FMT_RAW
        m_streamTypes     : STREAM_TYPE_AC3,STREAM_TYPE_EAC3,STREAM_TYPE_DTSHD_CORE,STREAM_TYPE_DTS_2048,STREAM_TYPE_DTS_1024,STREAM_TYPE_DTS_512
    Device 2
        m_deviceName      : Analogue
        m_displayName     : Analogue
        m_displayNameExtra:
        m_deviceType      : AE_DEVTYPE_PCM
        m_channels        : FL, FR
        m_sampleRates     : 48000
        m_dataFormats     : AE_FMT_FLOAT,AE_FMT_S32LE,AE_FMT_S16LE,AE_FMT_FLOATP,AE_FMT_S32NEP,AE_FMT_S16NEP
        m_streamTypes     : No passthrough capabilities
    Device 3
        m_deviceName      : Both
        m_displayName     : HDMI and Analogue
        m_displayNameExtra:
        m_deviceType      : AE_DEVTYPE_PCM
        m_channels        : FL, FR
        m_sampleRates     : 48000
        m_dataFormats     : AE_FMT_FLOAT,AE_FMT_S32LE,AE_FMT_S16LE,AE_FMT_FLOATP,AE_FMT_S32NEP,AE_FMT_S16NEP
        m_streamTypes     : No passthrough capabilities

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Playing AAC LC content:

Code

Creating audio stream (codec id: 86018, channels: 8, sample rate: 48000, no pass-through)
CAESinkPi:Initialize Format:24 Channels:8 Samplerate:48000 framesize:32 bufsize:76800 bytes/s=1536000.00 dest=PI:HDMI
CAESinkPi:SetAudioProps hdmi_stream_channels 0 hdmi_channel_map 13b3e4c8
CActiveAESink::OpenSink - SinkPi Initialized:
  Output Device : HDMI
  Sample Rate   : 48000
  Sample Format : AE_FMT_FLOATP
  Channel Count : 8
  Channel Layout: FL, FR, FC, LFE, BL, BR, SL, SR
  Frames        : 2400
  Frame Size    : 32

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Playing DTS-HD content, plays as 5.1:

Code

Creating audio stream (codec id: 86020, channels: 6, sample rate: 48000, pass-through)
CAESinkPi:Initialize Format:2 Channels:2 Samplerate:48000 framesize:4 bufsize:9600 bytes/s=192000.00 dest=PI:HDMI
CAESinkPi:SetAudioProps hdmi_stream_channels 1 hdmi_channel_map 00000000
CActiveAESink::OpenSink - SinkPi Initialized:
  Output Device : HDMI
  Sample Rate   : 48000
  Sample Format : AE_FMT_S16NE
  Channel Count : 2
  Channel Layout: RAW, RAW
  Frames        : 2400
  Frame Size    : 4

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The full log for LE9.2.6 can be found here.

**Da Flex** · May 30, 2021 at 6:11 PM Official Post

Do you have tried 2.0 output channels at the audio settings?

Does enable / disable audio pass-through make any difference?

AMoo-Miki · May 31, 2021 at 9:12 AM

Da Flex, 2.0 with FL and FR is output correctly.

I also tried disabling passthrough which was enabled earlier and the problem remains.

Comparing the logs from LE9.2.6 and LE9.95.3, i noticed that LE9.2.6 finds the AE_FMT_FLOATP but LE9.95.3 cannot find AE_FMT_FLOAT.

However, I have a feeling that the issue is not LE really and is in fact an issue with ALSA on RPi. I hope LE honors asound configs.

**Da Flex** · May 31, 2021 at 2:34 PM Official Post

Quote from AMoo-Miki

Da Flex, 2.0 with FL and FR is output correctly.

My point is different. 2.0 output channels doesn't mean you're just getting FL and FR. Instead all other channels are encoded at those two. If everything works right, more than 2.0 output channels are mapped correctly to the hardware, but I'm not sure about this. So please test this setup and report.

AMoo-Miki · May 31, 2021 at 7:42 PM

I am not sure if I understood what you were asking but here is what I did:

I changed the audio output settings to 2.0 and played an 8-channel test wave file. The output correctly identified front, back, and surround lefts and rights which it played all from front left and right; it skipped LFE which I guess is expected.

I apologize if that is not what you meant and am very thankful that you are helping.

I Switched back to 7.1 in audio settings of Kodi and tested the same file. While the channel layouts were like the AAC LC log where there was BC and UNKNOWN1, the input on SL was sent to BL and the input on SR was sent to RL; none of the surround speakers made any sound.

I did a speaker-test -c8 and the channel mixup exists there too.

Code

Playback device is default
Stream parameters are 48000Hz, S16_LE, 8 channels
Using 16 octaves of pink noise
Rate set to 48000Hz (requested 48000Hz)
Buffer size range from 16 to 40960
Period size range from 8 to 20480
Using max buffer size 40960
Periods = 4
was set period_size = 10240
was set buffer_size = 40960
 0 - Front Left
 3 - Front Center
 1 - Front Right
 5 - Rear Right
 6 - Rear Center
 4 - Rear Left
 2 - LFE
 7 - Unused

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**Da Flex** · May 31, 2021 at 9:35 PM Official Post

There is no option for channel mapping on LE.

FLAC, AAC and Vorbis can't be played with pass-through, so the switch makes no difference here. As a workaround, you could use PCM and pass-through.

Generally your issue seems to be a bug. You can try LE 9.95.4. If the bug remains, write a bug report.

It's still beta testing.

AMoo-Miki · June 1, 2021 at 8:14 AM

of course. thanks. I am convinced that this is an ALSA problem. I will try the 9.95.4 and will also spin a desktop Buster to see if the problem remains. Thanks for the bug report link

PS, in agreement with what you mentioned, even though I have pass-through configured, only TrueHD and DTS HD are being passed as RAW and played correctly through all 8 channels. All others go through PCM and the bad channel mapping occurs.

**Da Flex** · June 1, 2021 at 3:41 PM Official Post

The developer, I was talking with, said, they currently switch from VC4 to HDMI codec (whatever this means). It's possible that PCM pass-through has a mapping issue due to that change.

AMoo-Miki · June 1, 2021 at 10:45 PM

Thanks. I installed RaspiOS and did the speaker test and all the speakers worked correctly as expected. I will raise it as a bug.