S905 Libre ELEC 8.0.1C USB andio (amanero combo384) sounds looks like crackles

  • Hi,Everybody,

    First thanks  kszaq's hard work so we can use the good Libresystem for S905 TV box,
    The TV box I used hardware is S905M, 1G RAM, 8G ROM, 100M lan, 8189 Wifi.
    system is Libre ELEC 8.0.1C for S905/S905X.

    I used optic fiber before it works well, then I tried amanero combo384 usb audio to receive audio, here I found the sound have some strange noisy, like crackles along with normal sound, I compared the latest system 8.0.1C , it improved than old version, but still have some crackles sound, I tried to fix it, but I don't know why and so there I can not find a way to fix it.

    I checked wiki of kodi, found a stence, the decription looks like the issue I met, but I'm not sure, I seached google and I didn't find out solution.

    6.5 Known issues

    When your audio is much too fast or crackles a lot or passthrough only produces noise, you might have a broken driver in use. If this is the case, try to add tsched=0 to the udev loading section in /etc/pulse/default.pa to read like:load-module module-udev-detect tsched=0Audio devices are disappearing with pulseaudio 8.0 (Ubuntu 16.04) especially while running kodi and while using Adjust Refreshrate to match video. This is an issue with the module-switch-on-port-available module and will be fixed with pulseaudio 9.0, the fix sadly won't probably make it into Ubuntu 16.04. As a workaround please disable that feature by editing /etc/pulse/default.pa and commenting or removing load-module module-switch-on-port-available and reboot the system.


    I grab system log and wish you could found something it, I checked the log and found audio log didn't include the audio card information of amanero, so I used aplay -L to get the information and attached it in below:

    LibreELEC:~/.config # aplay -L
    null
    Discard all samples (playback) or generate zero samples (capture)
    default:CARD=AMLM8AUDIO
    AML-M8AUDIO,
    Default Audio Device
    sysdefault:CARD=AMLM8AUDIO
    AML-M8AUDIO,
    Default Audio Device
    front:CARD=AMLM8AUDIO,DEV=0
    AML-M8AUDIO,
    Front speakers
    surround21:CARD=AMLM8AUDIO,DEV=0
    AML-M8AUDIO,
    2.1 Surround output to Front and Subwoofer speakers
    surround41:CARD=AMLM8AUDIO,DEV=0
    AML-M8AUDIO,
    4.1 Surround output to Front, Rear and Subwoofer speakers
    surround50:CARD=AMLM8AUDIO,DEV=0
    AML-M8AUDIO,
    5.0 Surround output to Front, Center and Rear speakers
    surround51:CARD=AMLM8AUDIO,DEV=0
    AML-M8AUDIO,
    5.1 Surround output to Front, Center, Rear and Subwoofer speakers
    surround71:CARD=AMLM8AUDIO,DEV=0
    AML-M8AUDIO,
    7.1 Surround output to Front, Center, Side, Rear and Woofer speakers
    hdmi:CARD=AMLM8AUDIO,DEV=0
    AML-M8AUDIO,
    HDMI Audio Output
    default:CARD=Amanero
    Combo384 Amanero, USB Audio
    Default Audio Device
    sysdefault:CARD=Amanero
    Combo384 Amanero, USB Audio
    Default Audio Device
    front:CARD=Amanero,DEV=0
    Combo384 Amanero, USB Audio
    Front speakers
    surround21:CARD=Amanero,DEV=0
    Combo384 Amanero, USB Audio
    2.1 Surround output to Front and Subwoofer speakers
    surround40:CARD=Amanero,DEV=0
    Combo384 Amanero, USB Audio
    4.0 Surround output to Front and Rear speakers
    surround41:CARD=Amanero,DEV=0
    Combo384 Amanero, USB Audio
    4.1 Surround output to Front, Rear and Subwoofer speakers
    surround50:CARD=Amanero,DEV=0
    Combo384 Amanero, USB Audio
    5.0 Surround output to Front, Center and Rear speakers
    surround51:CARD=Amanero,DEV=0
    Combo384 Amanero, USB Audio
    5.1 Surround output to Front, Center, Rear and Subwoofer speakers
    surround71:CARD=Amanero,DEV=0
    Combo384 Amanero, USB Audio
    7.1 Surround output to Front, Center, Side, Rear and Woofer speakers
    iec958:CARD=Amanero,DEV=0
    Combo384 Amanero, USB Audio
    IEC958 (S/PDIF) Digital Audio Output

    Please help to tell me how to solve it, just need to adjust ALSA configuration or need kernel modification, I'm not sure about it, thanks for your support!

  • USB device support in the amlogic kernel 3.14 is limited. There currently is no newer kernel version available. If your box has no digital audio connector, you could try using an hdmi audio extractor to connect your receiver.


  • USB device support in the amlogic kernel 3.14 is limited. There currently is no newer kernel version available. If your box has no digital audio connector, you could try using an hdmi audio extractor to connect your receiver.

    Hi,mmpp,

    Thanks for your reply!

    Currently I can use optic fiber(SPDIF), I can wait update about the kernel, thanks!
    [hr]

    Hi,mmpp,

    Thanks for your reply!

    Currently I can use optic fiber(SPDIF), I can wait update about the kernel, thanks!

    I just checked Amoglic website, it looks like they have released new kernel for S905, may be we need to waiting to implement to compile the new kernel.

    arm-Kernel Info - Amlogic openlinux
    8. 2017-03-31 released:

    Edited once, last by johnzhang (April 6, 2017 at 3:14 PM).