[x86-64] No 2160p on JVC Projector

    Basically the title, but I just installed LibreElec Generic on the GMKtek G3 Plus. Everything is working fine, including displaying via HDMI to my PC monitor, and displaying through my JVC projector (connected to Marantz preamp) in the theater at 1080p. But as soon as I switch to 2160p the screen simply blanks out. I wait a few seconds, and it returns back to the earlier 1080p setting (as expected, since I was unable to confirm that 2160p was working). Does anyone have any ideas or suggestions? Bit of a bummer, as I was hoping to use this as the replacement for the Nvidia Shield Pro in the theater. Thank you!

    The problem description suggests you're trying to set the Kodi desktop resolution to 4K (and users typically pick 4K60) which you probably don't want to do. Have a read here first: https://wiki.libreelec.tv/configuration/4k-hdr

    If the device won't switch to any 4K modes (or perhaps modes above 4K30) for playback, the normal cause is HDMI cables that won't support the bandwidth required, or a mismatch between the colour output on the HTPC and input on the TV, e.g. TV only allows 4:2:0 input and you're sending 4:2:2 or some RGB format.

    The additional dice-roll on inexpensive Intel devices is that the HDMI outputs are often derived from DP using an LSPCON chip which has its own firmware (can be buggy or needing updates) which influences the capabilities of the HDMI chain as this is cheaper to manufacture than wiring up a dedicated HDMI display transciever on the board. Some users find they need to use the DP outputs with an external DP to HDMI adapter to avoid problems with the internal one. Of course, the external DP to HDMI convertor also has a chip (with firmware) so they are not all equal, but unlike the internal convertor you can order a few different ones from Amazon and then return them if they didn't work.

    For some users it all just works fine. Others have a more frustrating experience. We'd love to meet the Intel engineer who first came up with the idea of using LSPCON chips with their NUC designs (which everone has copied since). Preferrably in a dark alleyway so we can thank them properly for all the extra support work and frustration we've encountered since then.

    I don't believe that LSPCON is still used in Alder Lake+ designs.

    The display block in older Intel GPUs (Gemini Lake, Tiger Lake) could provide only one HDMI 2.0 port natively. Some of those NUC designs had two HDMI 2.0 ports, so they had to use a DP-to-HDMI converter. Some devices had one native port + one port via DP LSPCON.

    Thank you both! I am away from home right now, so I can’t test further, but when I get back I will try setting the Kodi UI to 1080p and then try to launch a few 4K video files. I “know” (or am pretty highly certain) that this is not a problem with HDMI cable or the receiver or projector capabilities as 1) it’s a high-end home theater that has five HDMI inputs through the chain, 2) the JVC projector/Marantz receiver combo has displayed 4K/60Hz content a million times (most recently through an Android AM6B+ running CoreElec, and finally, I tried the new NUC on three different HDMI cables (and then returned the previous devices to those inputs, which worked again). So, my best guess is that it’s an issue with LibreElec or perhaps the LSPCON chip mentioned earlier. Is there any sort of log or test I can do which might help diagnose the issue further?

    Update:

    Verified that the NUC works at 1080p for both UI and video playback, and in fact will play 4K videos (though reduced to 1080p during playback). This is for both 60 and 59.94 Hz. I had hoped that playing a 4K video would at least trigger 4K video playback, but no luck (just got the same blank screen for a few seconds before falling back to 1080p). Also removed the NUC and replaced the AM6B+ Android device with Kodi and played the same video, same high-end HDMI cable and verified it works fine.

    At this point I’m quite sure it’s not the HDMI cable, and am not sure what else I can check. Projector is JVC DLA-NX7, running through a Marantz AV8802 preamp, and I’ve never had issues with color output/input. Is there a specific test or log I can collect that might help? Happy to chase down whatever else I can if it’s helpful, with thanks!

    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

    Thank you for those clear instructions!

    I first turned on logging, then tried to change from 1080p to 2160p, both 60 and 59.94 Hz. That log is:
    https://paste.libreelec.tv/enormous-dory.log

    I realized afterward that I had forgotten to reboot the machine/restart Kodi. So I did that, and this time:

    1. Verified 1080p UI was showing
    2. Launched 4k movie, verified it played (though downsampled to 1080p)
    3. Attempted change to 2160p in settings (leaving 60 Hz already selected) - failed
    4. Changed Hz to 59.94 (succeeded)
    5. Attempted change to 2160p again, failed

    This second log is: https://paste.libreelec.tv/suitable-quail.log

    Hope this helps!

    Quote from Ozyman

    Hope this helps!

    Not much. Please repeat after creating a plain SMB mount to the device where you store media, then play something appropriate and 4K from that source using the Kodi 'Videos' view so we can see a playback event containing all the normal and useful ffmpeg/drm/Kodi media debug info that's being masked or suppressed by the Plex plugin you are using. In the log you've captured I can sort of figure out where playback probably occurred, but there's no useful info.

    Done. I had issues mapping an SMB share, but NFS worked fine, so I used that.

    To try and clean things up even more, I reset LibreElec to factory defaults (which also removed the Plex plugin - PM4K).

    Test:

    1. Set UI to 1920x1080P when connected to my PC monitor (so I could see UI)
    2. Moved NUC down to theater, and connected to Marantz/Projector HDMI chain.
    3. Powered on, verified I could view UI at 1080P.
    4. Turned on logging.
    5. Launched 4K movie via Videos view - played, but at 1080p (as verified by projector popup)
    6. Submitted log: https://paste.libreelec.tv/just-goblin.log

    I can find the playback in the log, so I think it worked. Note that I did *not* try to set the Kodi resolution setting again this time, just to keep things cleaner. I only tried playing the 4K video as suggested. Thanks again!

    Code
    2025-08-13 19:08:23.604 T:976      info <general>: ffmpeg[0x208aae90]:   Stream #0:0: Video: hevc (Main 10), yuv420p10le(tv, bt2020nc/bt2020/smpte2084), 3840x2160 [SAR 1:1 DAR 16:9], 23.98 fps, 23.98 tbr, 1k tbn (default)

    ^ media is detected as 4K23.976 (10-bit, with a colourspace normally associated with HDR)

    Code
    2025-08-13 19:08:23.740 T:979     debug <general>: CRenderManager::Configure - change configuration. 3840x2160. display: 3840x2160. framerate: 23.98.
2025-08-13 19:08:23.745 T:892     debug <general>: DeleteRenderer - deleting renderer
2025-08-13 19:08:23.745 T:892     debug <general>: LinuxRendererGLES: Cleaning up GLES resources
2025-08-13 19:08:23.745 T:892     debug <general>: SetHDR: setting connector colorspace to Default
2025-08-13 19:08:23.745 T:892     debug <general>: LinuxRendererGLES::Configure: fps: 23.976
2025-08-13 19:08:23.745 T:892     debug <general>: SetHDR: setting connector colorspace to BT2020_YCC
2025-08-13 19:08:23.745 T:892     debug <general>: LinuxRendererGLES::Configure: HDR passthrough: on

    ^ then it flags a renderer with [email protected] and appropriate colourspace, but have you enabled "adjust reresh" ? - If yes it will output using the whitelist (not configured) or best guess at the right mode. If not, it will scale the output to the desktop res (1080@60). So make sure adjust-refresh is enabled and configure the whitelist as per the wiki article.

    Once done, if you run kmsprint on the SSH console before playback it will show DRM connector properties as 1080@60, and during playback it should show them to be [email protected]?

    Ok, some good progress, but new oddities as well. I checked, and Adjust Refresh was not enabled. I turned that on, but just for start/stopping videos so that I could leave the UI at 1080x1920p. I also turned on the whitelist, and enabled the following per the wiki recommendation:

    3840x2160 @ 60/59.94/50/30/29.97/25/24/23.976
    1920x1080 @ 60/59.94/50/24/23.976

    Once done, the 4K videos launch and play as expected. However, now I get an occasional audio pause or distortion every 10-15 seconds. This is for streaming passthrough audio, so I am guessing it *might* be because I'm playing from a network share directly, and not via Plex and its presumable streaming/buffering capabilities?

    Hoping to get some feedback on that new issue, I turned on logging and rebooted the NUC. Unfortunately, the NUC would no longer boot into Kodi, and instead showed the same blue screen I saw earlier (before I enabled the Adjust Refresh and whitelist resolution recommendations). The first time I saw the NUC bios screen and briefly saw the LibreElec logo, but then had to hard shutdown the NUC (held down power button for 5+ seconds) to try again. Afterward, didn't even see the LibreElec logo upon powering up - only saw the bios screen briefly.

    So, I powered the NUC down and brought it back up to the PC monitor and plugged back in. And lo and behold, somehow the Video UI resolution had been set back to 2160p (definitely not by me), which at first seemed to help explain the blue screen - *but* then I realized I had previously set the Adjust Refresh on (for starting/stopping videos) and the Whitelist refresh settings, so in theory it shouldn't matter. I checked those latter settings again, and verified they were still set and had not automagically changed from under me (like the UI resolution setting did).

    The likely long log can be found at https://paste.libreelec.tv/dynamic-crab.log

    In summary:
    1. would love input on what the audio issue might be (if possible)
    2. am mystified as to the unexpected settings UI resolution change to 2160p (first of all)
    3. and, surprised why it wouldn't work with that resolution since the videos seemed to work with the Display Refresh and Whitelist changes? Perhaps this last one is because Adjust Refresh is on for only starting/stopping videos, and not called on first booting into Kodi?

    Thanks again for all of the help!

    I'm wondering if the audio glitch is similar to the N100 issues here: https://github.com/LibreELEC/LibreELEC.tv/pull/8588 - the script in that PR is not going to be merged as it's too much of a hack, but you could copy/paste it locally and experiment. It basically finds the active DRM connector and limits the max bits-per-pixel to 10-bit as 12-bit seems to cause issues. The root cause is unknown but I have a hunch it's related to bandwidth and UHD video + HD audio maxes out something resulting in audio dropouts.

    You might want to add something like video=HDMI-A-1:1920x1080M@60 to kernel boot params in syslinux.cfg in case (for reasons unknown) the box is trying to use a problematic 4K mode. This will clamp initial kernel DRM output to 1080@60 to stop that. There's no impact on Kodi switching to 4K during playback later.

    I've tried running the script located in post 46 of this thread:

    Post

    RE: Intel Alder Lake 2160p @ 23.976 Hz passthrough HD Audio dropouts (i7-1270p/N100)

    After some more help and this time from jernej . Thank you.

    I have now a script to fix the audio problem for any LE11/12 without extra binary. The same script works on LE11 or 12.
    wget https://raw.githubusercontent.com/sky42src/LibreELEC.tv/11.80.5-240204/projects/Generic/filesystem/usr/bin/intel-gpu-max-10-bit.sh && chmod +x intel-gpu-max-10-bit.sh && ./intel-gpu-max-10-bit.sh

    I opened a pull request to make the helper script part of official LE.
    …
    sky42
    February 4, 2024 at 9:42 PM

    As far as I can tell, this is the same fix you mention above for the N100 issues. Will test and update with results.

    One key question - are these script's changes persistent? Or do they need to be reapplied somehow every time the box power cycles or reboots?