NUC6CAYH Audio problems

  • hi all

    Ive just updated my n2820 nuc which worked fine, to a NUC6CAYH. This decodes hevc, which the last one doesn't.

    Im having some trouble with the audio bitstreaming. Dts and dolby digital seem to work ok, but the lossless ones dont. I get no audio.

    Ive updated the bios and ive updated the hdmi firmware.

    Ive searched around and found others with audio issues on this NUC. There is some mention of an audio dsp setting in bios, that i dont have, and some talk about a "blacklist" which i dont understand. This was years ago though, and there was talk of adding the fix into libreelec, so surely this has been fixed by now?

    If i change the audio settings to fixed, from optimised, i get audio, but no bitstreaming, i just get multi channel in on the AV receiver.

    Ive noticed that when the audio doesnt play, the refresh rate change happens a few seconds after the video starts. It should do this right at the beginning. Not sure if this gives any clues.

    Any ideas?

    Thanks

  • Ive noticed that when the audio doesnt play, the refresh rate change happens a few seconds after the video starts. It should do this right at the beginning. Not sure if this gives any clues.

    This could indicate a bottle neck in data transmission. A slow cable is often the issue. So check the HDMI standard of your cable. It should be conform to HDMI 2.0 or 2.1 to handle video AND high speed audio.

  • I see. So you play 1080p with HD audio?

    You can also play around with the amount of audio output channels in LE's settings. Sometimes 2 channels are required.

    If this doesn't work, we should dig deeper with a log file.

    Please provide a full debug log.

    How to post a log (wiki)

    1. Enable debugging in Settings>System Settings>Logging
    2. Restart Kodi
    3. Replicate the problem
    4. Generate a log URL (do not post/upload logs to the forum)

    use "Settings > LibreELEC > System > Paste system logs" or run "pastekodi" over SSH, then post the URL link
  • Hi.

    Yes, currently 1080p plasma with a AVR that supports DTS MA and Dolby TrueHD.

    The old system worked fine. but would struggle a bit on some 1080p HEVC, this should decode those in hardware

    I tried selecting 2.0, 5.0 and 5.1 in the audio settings, no change.

    Log file: (if ive done it correctly)

    http://ix.io/4a4J

    The thing i mentioned about the refresh change not happening at the start of the file, only seems to happen when i play one of the dolby/dts demo file. These are quite short, so perhaps that has something to do with it.

    i can post a log of that too, i dont know if it would overwrite the previous log?

    Thanks for your help


    another thing, when i installed libreelec on the nuc, it was connected to my pc monitor, not the AVR and TV. Could that be the issue?

    Edited once, last by Champ222: Merged a post created by Champ222 into this post. (September 9, 2022 at 11:42 PM).

  • The log looks good to me. You can upload more logs without problems, but there is currently no need.

    Maybe the wrong Linux driver was loaded:

    Code
    Sep 09 22:05:46.708885 LibreELEC kernel: ACPI: Added _OSI(Linux-Lenovo-NV-HDMI-Audio)

    Eventually other users have "blacklisted" that driver to load the right one. I'm no kernel expert, I don't know.

    Our audio guru just went into holidays. It could take a while to answer this.

  • i tried the latest nightly, installed to a different drive, its exactly the same unfortunately

    although saying that, trying to playback the demo files with the DTS-MA and dolby TrueHD no longer breaks the audio. with the previous install, i'd lose the ticks in the UI or the sound would go all tinny. It doesnt seem to do that with the nightly.

    Who is the Audio Guru? just so i can keep an eye out for posts from them.

    Thanks

    Edited once, last by Champ222 (September 10, 2022 at 11:06 PM).

  • HiassofT is the audio guru, and he is in holidays. If you want to do something, do a research about your hardware, and which Linux driver is needed for HDMI. To "blacklist" your current driver could be the right path.

  • ahhh, he is still on holiday, i thought i saw him active on the forum.

    I will try and do some research about the driver.

    I saw some posts from a few years back about the blacklist. I pasted in the suggested command, but it didnt appear to change anything.

    When you say blacklist, what are we doing here? Forcing it to use that driver? Or to not use that driver? Its not a term ive heard anywhere else.

    Thanks

  • Ive come across this:

    98797 – [BXT/KBL] - HDMI - HD audio passthrough dont work

    around comment 110, there is mention of a working fix, but then comment 124 suggested issues with adjust Refreshrate to match video. Then the thread ends. I cant remember if i tried it with that setting off... Its the first setting i set, as i hate the judder.

    ive found an earlier HDMI firmware. I updated to 1.77 which appears to be the latest. All the "fixes" seem to refer to 1.66. All chatter on this issue seems to be around 2017, which is what made me think this should be fixed by now. I still have the windows install on the old SSD i think, so i'll try rolling back to an earlier HDMI version and see if that helps.

    Edited once, last by Champ222 (September 14, 2022 at 2:32 PM).