NUC11PAHi5 HD audio passthrough problems (and AAC 5.1)

    I recently bought a NUC11PAHi5 to replace my old gen 3 NUC. I installed LE 10.0.1 and configured the new device to exactly match the settings I have on the old NUC (also LE 10.0.1). The NUC is connected to a Denon AVC-X3700H via HDMI. I did some tests using a few Dolby and DTS trailers with various audio formats. To my surprise the files with Dolby TrueHD, Dolby Atmos, DTS-HD Master and DTS:X produced no sound at all. I also discovered that files with AAC 5.1 didn't produce any sound either. After a failed test I couldn't get any sound at all from the NUC11, even with files that had worked previously, until after a reboot.

    My old gen 3 NUC has no problems at all with passthrough of the above mentioned HD audio formats. The amplifier receives and identifies all the signals correctly. AAC 5.1 also works - the amplifier identifies the signal as 5.1 channel PCM. I literally just pull the HDMI cable from the NUC11 and connect it to the old NUC and it works... I have compared the settings with a diff tool to be sure I'm not missing anything and they are the same.

    I have updated the NUC11 with the latest (0043) BIOS from Intel and also updated LE to 10.0.2. I even tried a recent LE 11 nightly build. Still no joy... I then installed Windows 10 and Kodi 19.4 on a second drive. Annoyingly that works (using WSAPI) and I get sound from the HD audio files as well as the files with AAC 5.1. I'd rather not resort to using Windows though...

    So it seems to me that the NUC11PAHi5 and LE 10/11 don't play well together. Is this a known problem? Are there any solutions or work-arounds I can try? (BTW. The NUC11PAHi5 is one of those NUCs with HDMI -> PCON -> DP1.4 if that matters.)

    Quote from smp

    Go to "Passthrough output device" setting and switch to the correct port.

    Unfortunately, not as easy as that. Passthrough generally speaking works, just not for the audio formats I mentioned.

    I have selected the passthrough output device where the Denon amplifier is shown as connected (ALSA: HDA Intel PCH, DON DENON-AVR on DisplayPort #0) and enabled passthrough of all the listed formats. (AC3, E-AC3, DTS, TrueHD, DTS-HD). Dolby Digital and DTS passthrough works just fine. Passthrough of TrueHD and DTS-HD does not. If I press the "Info" button on the Denon remote during playback of TrueHD or DTS-HD the signal is shown as "Unknown".

    I'm guessing the reason for the amplifier being listed as connected to "DisplayPort #0" is the protocol conversion. The block diagram for NUC11PAHi5 shows HDMI 2.0b -> PCON -> DP1.4 -> Tiger Lake UP3 (1135G7 with Iris Xe).

    Then there's the problem with AAC 5.1 which isn't related to passthrough. If I play content with AAC 2.0 the Denon identifies it as 2-channel PCM and I get sound. Playback of content with AAC 5.1 results in "Signal: Unknown" and no sound.

    Doing the same tests with my old NUC (with a gen 3 i3 CPU) everything works as expected. Passthrough of TrueHD/DTS-HD works and AAC 5.1 is received as 5.1-channel PCM. Same version of LE (10.0.1) in both NUCs, same settings, everything downstream from the NUCs is the same.

    Edited once, last by Kraprot (March 21, 2022 at 8:46 AM).

    Hi everyone,

    I have a similar problem with my intel miniPC (Intel Core i5 8265U + Intel UHD Graphics 620).

    I'm using LE 10.0.2, tried version 9 too and it's the same problem.

    Passthrough is enabled and the right source is selected (Kodi even detect my AV name on the source).

    My AV supports DTS, DTS-HD, Dolby, DD+, True HD, Atmos, etc ... All of these formats work fine from my blu-ray player for instance.

    In LE, passthrough does not work... The AV displays "Analog" instead of displaying DTS or whatever and no sound is played.

    If I disable passthrough, I have sound, MCH PCM (decoded by Kobi). But the sound is poor and the goal to use an AV is to make it decode those.

    Any hint ? What could I send to help you help me with this issue ? (debug logs: http://ix.io/3WTh).

    In addition, I'ld like to add that this PC is able to correctly perform passthrough as I successfully tested it in Windows. However I would really like to avoid using Kodi in Windows ...

    Thank you,

    Benjamin

    since this and similar issues are still persistent, I am assuming that NUC support has been silently dropped.

    Even LE 12 doesn't seem to understand the hdmi channels available on a NUC, 11 the number of which seem to increase every time I fail top playback something.

    Interestingly, it used to work on le10, somewhat, since there you can also select the video out (not anymore on le11), but it has stopped now to the point that no hdmi audio is available at all. I don't know if the hardware is somehow rotting away, but I cannot convince myself to believe that.