Stereo passthrough issue in L9 and Odroid C2

  • I upgraded my Odroid C2 with the latest L9 image and everything went smoothly, with the exception of some audio issues and reconnecting my bluetooth remote control (that's another story). At first I had no sound, however through some setting changes I managed to get audio for all files, with exception of those with 2.0. I have a 5.1 setup and the audio is passed through to my new AV receiver (Marantz SR6013). The only way I can get sound for 2.0 files and live tv is to tick the stereo upmixing option.


    In my L8.2.5 installation I didn't have the stereo upmixing ticked and I got stereo pass through. Has anyone else found this issue with L9 and Odroid C2?


    My audio settings are:


    Audio Output Device: HDMI

    Number of channels: 5.1

    Output configuration: Best Match/b>

    Stereo upmix: Enabled (only way to 2.0 audio)

    Normalize levels on downmix: Disabled

    Resample quality: Medium

    Keep audio device alive: 1 min

    Enabled passthrough: Enabled

    Passthrough output device: HDMI

    All audio formats are enabled

    Edited once, last by zanlation ().

  • I have the same problem with Odroid C2. It stopped working with the LibreELEC (Leia) 9.0.0 upgrade. I have tried a new install but it didn't help. FLAC and mp3 audio files work, but videos with stereo sound don't. Only with stereo upmix do I get any sound.

  • Can also confirm this.

    At the very least the ability to turn upmix on/off from the in movie interface is required.

  • I have a similar problem after upgrading to 9.0:
    A WeTek Play 2, connected via optical out to a pioneer receiver.

    AC3 and DTS passthrough enabled in the Kodi settings. AC3/DTS works, but all other audio not. Tested with TV streams from TVHeadend and other video files.
    In 8.2.5 there was no problem with the following settings (it is in german, sorry):



  • I tested with a fresh LE9 installation yesterday.

    And there I have not the same problem(UPDATE 16.02.: that is incorrect, tested again, both have a problem with 48kHz sample rate) .

    First of all the new installation sets the audio device default to "AML-M8AUDIO Analog" on my WeTek Play 2. The Box is connected via optical out to a Pioneer receiver.

    I switched it to "AML-M8AUDIO, HDMI".

    It was then possible to play a video file with AAC 2.0 (Details from VLC: AAC 44100Hz stereo 96kbps, 32 Bit per Sample ), mmmhh interesting.


    I switched then the SD card to the upgraded LE9, problem still there.

    I changed the audio device to "AML-M8AUDIO Analog", played the video with AAC 2.0 and audio was there -> cunfusion, why did I get audio on a digital output if the audio device is setup to "Analog"?


    Then I started a video with DTS and the passthrough was also working. I was happy then, but unfortunately too early.

    I started the video with AAC 2.0 again and now the audio was "dull", played in lower frequency and cuts every few seconds.

    Further the "click" sounds in the main menu had this dull sound, too. I had to switch the audio device to bring the menu sound back to the normal sounds.


    In result I can choose between 2 problems:
    - no audio for stereo streams if the audio device is set to "AML-M8AUDIO, HDMI"

    - corrupted audio for stereo streams if the audio device is set to "AML-M8AUDIO Analog"


    Log for the "no audio" case:


    Log for the corrupted audio case:

    Edited 3 times, last by viper4le: Correction ().

  • Hello,


    Exactly the same problem for me on my Wetek play 2. Sound works great on movie (DTS and DD) but not on pvr for example (2.0 channel).


    Wtek is connected with HDMI to Onkyo receiver passthrough enable.


    For the moment i've downgrade my wetek to 8.2.5 => No problem.

  • Similar issue, same setup (Odroid C2, latest LibreELEC), except that in my case I'm having problems specifically with aac/mp4 files, video and audio. Other formats, stereo or not, work fine.


    Anyway, so far, I've found 3 workarounds, but none of them is ideal.


    1-Play everything through the default/analog output. This doesn't affect passthrough signals, but plays music files through Odroid's DAC, which sounds considerably worse than my AVR's DAC.


    2-Enable "stereo upmix". This makes aac/mp4 play, but will upmix everything that doesn't passes through, including my music files. Far from ideal, in fact, I'm yet to find any upmixing process that sounds good.


    3-Enable "stereo upmix", reduce number of channels to 2, enable "Dolby Digital Transcoding". When you reduce the number of channels to 2, a new option called "Enable Dolby Digital Transcoding" shows up under "Passtrough" settings. This allows video files encoded with aac/pm4 to be properly decoded by the AVR...Again, the downside is that music files are still processed by Kodi; They're not really upsampled, since there are just 2 channels selected, but are still being unpleasantly processed.


    To sum up, the problem boils down to playing music. Every one of the above workarounds "solves" the "video without sound" issue, specially option 3. However, in every one of them music quality is still being affected either by Odroid's DAC or Kodi internal processing.


    If you ask me, this is a bug.

    Edited once, last by Morguito ().

  • I can confirm that CoreELEC doesn't have this issue.


    I've started using it yesterday and it's working just fine.

  • It's a 'known' bug though, it's not worth fixing until we get a new kernel that isn't 3.14.

    And when might that be? Will the kernel be changed within the next LE 9.0.x or rather with LE 10 in 3 years?


    Currently LE9 works more like a beta on the Odroid C2. I can view exactly one video file with sound and have to reboot before playing the next one.

  • And when might that be? Will the kernel be changed within the next LE 9.0.x or rather with LE 10 in 3 years?


    Currently LE9 works more like a beta on the Odroid C2. I can view exactly one video file with sound and have to reboot before playing the next one.

    I've been using CoreELEC since my last post and it's running smoothly. You should try it.

  • When switching from Libreelec to CoreELEC, can you just place the CoreELEC file in the Libreelec "updates" folder ?


    Or should someone do a Backup, Fresh install and Restore ?

  • When switching from Libreelec to CoreELEC, can you just place the CoreELEC file in the Libreelec "updates" folder ?


    Or should someone do a Backup, Fresh install and Restore ?

    I wouldn't recommend that. The guys from CoreELEC team don't as well.


    The backup route is more appropriate, I think.