RPi 4/5 + Denon AVR - 4k60 'No Signal' issues

  • With resolution set to 3840x2160 @ 30FPS, I have not had this issue occur once in the last 2 weeks. The UI is more sluggish but its not slow. I always use 'adjust display refresh rate' on start/stop as well.

    There's a problem with 60FPS output, how do we work out if its a Denon problem or a Pi problem though.... Could run directly into the TV for a while I suppose but this may be a false test as I won't be passing through DTS/Dolby HD etc.

  • The latest LE12 nightly (since https://github.com/LibreELEC/LibreELEC.tv/pull/8616) would be interesting to test as it contains some changes to correct some EDID issues seen. No ideas if this is one of them, but would be good to rule in or out.

    RPI4@2160p@60Hz/59.94Hz->X3800H->OLED83C37LA: same beahavior: 4/5 to 6/7 of time; no signal
    RPI5@2160p@60Hz/59.94Hz->X3800H->OLED83C37LA: same beahavior: 4/5 to 6/7 of time: no signal

    RPI4@2160p@30Hz/29.97Hz->X3800H->OLED83C37LA: no problems
    RPI5@2160p@30Hz/29.97Hz->X3800H->OLED83C37LA: no problems

    Settlings like" hdmi_force_hotplug=1" in config.txt also have no effects.

  • Are you able to test directly to TV without the Denon? I can do so when I get home later.

  • Today i tested again a bit more.
    For every Test involving the Denon-Receiver i used 3 diffrent HDMI-Cables and got all the time the same Results.
    1) Mini-HDMI->HDMI Cable supporting 2.0 Standard, 2m
    2) Mini-HDMI->HDMI Cable supporting 2.1 Standard, 2m
    3) Mini-HDMI to HDMI-Adapter and a HDMI-Cable (both supporting 2.1 Version), 2m

    For the Test connecting the Raspberrys direct to the TV i even used some HDMI-Extension-Adapters with a resulting Cable-Length of 4m. HDMI support was 2.0 and 2.1

    Other settings:
    Denon AVR x3800H set to:
    - HDMI-Control: ON, everything else: OFF
    - 4k/8k-Signal Format: Extended
    - HDCP: all set to 2.3
    - Upscaling: off

    Pi4 and Pi5 set to:
    - CEC-Adapter: Disabled
    - Resolution: 3840x2160 @Hz of Testsetup
    - max-Gui-Resolution: 1080

    TESTS:
    ---------
    Raspberrys direct to TV:
    RPI4@2160p@30Hz/29,97Hz/60Hz/59.94Hz->OLED83C37LA: no problems
    RPI5@2160p@30Hz/29,97Hz/60Hz/59.94Hz->OLED83C37LA: no problems

    Raspberrys to AVR and AVR to TV:
    RPI4@2160p@30Hz/29.97Hz->X3800H@HDMI1/2/3/4/5/6->OLED83C37LA: no problems
    RPI5@2160p@30Hz/29.97Hz->X3800H@HDMI1/2/3/4/5/6->OLED83C37LA: no problems

    RPI4@2160p@60Hz/59.94Hz->X3800H@HDMI1/2/3/4->OLED83C37LA: same behavior: 4/5 to 6/7 of time; no signal
    RPI5@2160p@60Hz/59.94Hz->X3800H@HDMI1/2/3/4->OLED83C37LA: same behavior: 4/5 to 6/7 of time: no signal

    RPI4@2160p@60Hz/59.94Hz->X3800H@HDMI5/6(Aux1+Aux2)->OLED83C37LA: same behavior: 4/5 to 6/7 of time; no signal
    RPI5@2160p@60Hz/59.94Hz->X3800H@HDMI5/6(Aux1+Aux2)->OLED83C37LA: no problems

    The only diffrence for the HDMI-Ports of the X3800H i found in the manual is, that HDMI5/6 doesnt work on ZONE2(page 270).
    Other specific diffrence (like for the X2800HDAB that 8k is only supported on HDMI4/5/6) i didnt found.
    But there is definitly a diffrence. My bet is, that HDMI 5/6 accepts lower HDMI-Signal Power or something like that and that the Raspberrys HDMI-Signal Strenght is somehow to low for the Denon-AVR.

    https://www.raspberrypi.com/documentation/…config_txt.html says something about the option "config_hdmi_boost" for the config.txt but that this option will be ignored for the Pi4. Will that also be ignored for the Pi5 ?


    Oh and btw: i also checked if the AppleTV4k, and the RTX3080 worked on all HDMI-Ports in 2160p@60Hz.
    They do without any Problems. (The RTX 3080 was even with a 6m HDMI2.0 Cable connected to all HDMI-Ports)

  • The pi devs are currently looking into an issue related to loss of HDMI sync. It's not specifically about 4K60, but you never know, it might be related /shrug

  • The pi devs are currently looking into an issue related to loss of HDMI sync. It's not specifically about 4K60, but you never know, it might be related /shrug

    thanks

    On the settings there is a resolution option and then max ui res. Whats the difference? I assumed the resolution option is only for UI anyway or is that for videos also?

  • thanks

    On the settings there is a resolution option and then max ui res. Whats the difference? I assumed the resolution option is only for UI anyway or is that for videos also?

    If you don't have whitelisting of different resolutions enabled - then Kodi will run at a fixed output resolution (with only frame rates optionally changing if you have the Player setting enabled to change refresh rate on Start or Start/Stop etc.)

    The UI resolution setting allows you - I believe - to run the UI at a lower resolution than the output.

    So you could run with permanent 2160p output - with frame rate (but not resolution) switching for 23.976/24/50/59.94/60 etc., with UHD/4K video played at UHD, and other content upscaled to UHD by Kodi, but with the Kodi UI running at 1080p resolution (upscaled to 2160p)


    If you whitelist 2160p, 1080p, 720p etc. resolution output modes at various framerates - then Kodi will switch to 1080p output when playing 1080p content, 720p when playing 720p content etc. However this will only happen if you have whitelisted suitable modes.

  • If you don't have whitelisting of different resolutions enabled - then Kodi will run at a fixed output resolution (with only frame rates optionally changing if you have the Player setting enabled to change refresh rate on Start or Start/Stop etc.)

    The UI resolution setting allows you - I believe - to run the UI at a lower resolution than the output.

    So you could run with permanent 2160p output - with frame rate (but not resolution) switching for 23.976/24/50/59.94/60 etc., with UHD/4K video played at UHD, and other content upscaled to UHD by Kodi, but with the Kodi UI running at 1080p resolution (upscaled to 2160p)


    If you whitelist 2160p, 1080p, 720p etc. resolution output modes at various framerates - then Kodi will switch to 1080p output when playing 1080p content, 720p when playing 720p content etc. However this will only happen if you have whitelisted suitable modes.

    thanks makes sense

    also this issue is not related to resolution.

    I get no signal issue even on 1080p at 50hz. Only goes away if you use 30hz. Which makes skin less smooth.

    Edited once, last by Nekromantik (April 29, 2024 at 7:04 PM).

  • Glad I found this topic. I set up my new system last weekend including a new Denon X3800h + LG TV. I prepared my RPi5 with Libreelec 12 Stable yesterday and found I'm having the same issue. No matter what, I can't get a signal when switching inputs, unless I reboot or set to 30Hz. UI is definitely more sluggish with 30Hz but I guess there's no other workaround for now.

    Maybe there's a proper fix possible at some point when the issue is found, I would be happy to help in any way I can.

  • The pi devs are currently looking into an issue related to loss of HDMI sync. It's not specifically about 4K60, but you never know, it might be related /shrug


    This is interesting. But how do we go about reporting this thread as a bug for investigation as we have no idea currently if it’s on anyone’s radar for investigation?

  • This thread is known to devs but since none of them have an afflicted AVR themselves it's not something that's easily tested. If the current investigation comes up with anything (nothing yet, and it's unlikely to be quick) then we'll flag the change and have you all test something to see if the issues are related. In short: /shrug

  • Glad I found this topic. I set up my new system last weekend including a new Denon X3800h + LG TV. I prepared my RPi5 with Libreelec 12 Stable yesterday and found I'm having the same issue. No matter what, I can't get a signal when switching inputs, unless I reboot or set to 30Hz. UI is definitely more sluggish with 30Hz but I guess there's no other workaround for now.

    Maybe there's a proper fix possible at some point when the issue is found, I would be happy to help in any way I can.

    The workaround is to use AUX1/AUX2 and then you can put the UI at 60hz. I haven't had any issues with this configuration and you can rename the inputs so although it's odd to be forced to use those ports, it has been smooth sailing as long as you plug into one of those.