RPi 4 + Denon AVR - No Signal until source switch

    Hi all, I have a small issue where upon turning on my TV/AVR (Pi is on 24/7), I have to change away from and back to the RPi source in order to get a signal. AVR is a Denon AVR-X 3600H.

    If the RPi has been idle for sometime, and my Denon AVR starts up with the TV input selected (usually use the TV remote power button to turn on), changing to the RPi/LE source results in 'No Signal'.... I then change the source to something else, then back to the RPi/LE and I have signal. I have CEC enabled on the TV, AVR and the Pi. I usually use the TV's power button on remote to turn the TV and AVR on/off in one. Kodi will switch the AVR source and control volume via CEC, I understand it doesn't turn off or on with it though which is fine.

    Any ideas what the cause of this is? A setting on the RPi? Or something on the Denon AVR? Its not the end of the world, but is slightly annoying and takes away from the 'slickness' of my living room media set up having to do the remote juggle.

    I've found my Pi 4 and Pi 5s both confuse my Denon AVR-X2400H + Sony TV 49XF900? combo (haven't tried with my new LG OLED yet) does something similar. When the Pi boots you see the LibreElec splash screen and then get corrupt video (sometimes no signal on the TV, often digital shash).

    I found disconnecting the Pi's HDMI output and reconnecting (Hot plug force?) re-establishes a video display that's robust from then on as frame rates and resolutions change (I'm using a Pi Foundation Micro HDMI to HDMI short cable and then an Amazon HDMI 2.0b Premium Certified cable to the AVR, so break the connection at the in-line HDMI junction between the two cables)

    I think I've seen something similar with this combo when I change screen resolution and/or frame rate settings in Raspberry Pi OS - so suspect it's something to do with underlying HDMI handling that the Pi and Denon don't agree on.

    I got a similar Experience with a Denon X3800H, Pi4 and LG83C37LA while using the Pi-Foundation Micro-HDMI-Cable to the AVR.
    It got more and more worse if i set the PI4 via config.txt to 60fps. So i stay on 30fps

    So far it got better after using a Micro-HDMI-to-HDMI-Adapter directly at the PI4 and a 2.1HDMI-Cable to connect the PI4 with the AVR.

    My other settings are:

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

    Pi4 set to:
    - CEC-Adapter: Disabled
    - Resolution: 4096x2160p, 30fps (just keep the standard)
    - max-Gui-Resolution: 1080

    Thus i only have "no signal" at a chance on about 1:40 if i start and stop HDR-Videos immedtiatly but not anymore after changing the input on the Receiver.
    And if that rare case will happen, all that i need to do is to stop/start the video again to get again the HDMI-Connection.

    Hape that helps a bit

    PS: At weekend i will get the new Pi5 and will test if that will happen here also.

    Yup kind of the same here with RPi2 (not anymore), RPi4, RPi5, i3-8100, Vero 4k+ and very new Intel N100 all connected to X6700H to LG 55E6D. It is not the Pis it is Denon i fear. Intel is slightly less annoying . The X4500H before was not much better. I have all HDMI CEC off. The RPis and Denon do not really like each other. So far I did not find anything, but I leaned from you guys Denon Input switch helps. Did not know or try that before. Thanks.

    Quote from chewitt

    I'd use the 3840 "4K" modes: have a read here: https://wiki.libreelec.tv/configuration/4k-hdr

    Yep - 100%. All consumer '4K' content and displays are 3840x2160 (also known as UHD), not 4096x2160 (technically '4K' but not what people call 4K in the consumer space)

    My issues with Pi 4B/5 and Denon AVR-X2400H were in 3840x2160 modes (I never use the default and annoying 4096x2160 resolution).

    However it's early days but I recently also upgraded to a Denon AVR-X2800H (as I needed HDMI 2.1 support for a 2160p120 PS5 and our new LG TV) and things MAY have improved.

    Yesterday i got my Pi5 with a passive cooling-case and tested the described behavior.
    I could confirm, that the Denon-AVR will get confused if the Pi4 or Pi5 runs at 60Hz.
    It makes also no diffrence if a HDMI2.0 or HDMI2.1-cable is used or if the resolution is set to 3840x2160 or 4096x2160.
    In 1/4 of all cases the signal will be lost if i switch the Input on the Denon-AVR.

    With a refresh-Rate of 30Hz of the Pi4 and Pi5 the Problem is not gone but happens a lot less.

    So far i got not signal-loss while changing the Input on the Denon-AVR, but as described above it could happen in rare circumstances while start/stopping a Video with HDR. If that happens the Connection will be reestablished if i just press play/stop on the Remote.


    PS: I didnt tested CEC so far, because i always use a Harmony One as Remote for all Devices and thus i dont need CEC.

    Quote from andirama

    PS: I didnt tested CEC so far, because i always use a Harmony One as Remote for all Devices and thus i dont need CEC.

    When you said you've not tested CEC - can I check that means you have CEC disabled on the Pi and other devices - or you've just not tested remote control pass-through (which is a tiny part of CEC)?

    Edited once, last by noggin (January 14, 2024 at 2:29 PM).

    Quote from noggin

    When you said you've not tested CEC - can I check that means you have CEC disabled on the Pi and other devices - or you've just not tested remote control pass-through (which is a tiny part of CEC)?

    On Pi:
    - CEC-Adapter: deactivated.
    On Denon AVR:
    - HDMI-Control: ON, everything else: OFF

    I had the exact same problem as described in the first post. My setup is Pi 5 8GB connected to Denon AVR X2800HDAB connected to Sony Bravia XR55A80L. If the Pi source was selected/active on Denon while booting up Pi everything worked fine. As soon as I changed the source on Denon and then tried to get back to Pi I would not get video (No signal) in 50+% cases. Audio, on the other hand, worked (I could hear UI sounds).

    That was the case as long as I had Pi connected to CBL/SAT or Media Player HDMI input on Denon. Moving Pi to AUX1 or AUX2 HDMI input (two of three 8K ports on Denon), for some reason, solved the issue. Switching to Pi source now works flawlessly.

    I'm running Pi at 3840x2160, 60Hz with this added to the cmdline.txt:

    Code
    video=HDMI-A-1:3840x2160M@60D,margin_left=0,margin_right=0,margin_top=0,margin_bottom=0

    In addition to that, I added the following to the config.txt:

    Code
    hdmi_force_hotplug=1
disable_overscan=1

    Here is my workaround to force HDMI reconnect that i use for some time now on all my devices RPi4, RPi5, Vero 4k+, Intel N100

    For this to work you need System -> Player -> Videos -> adjust display refresh rate -> On Start (or Start/stop should work too)

    SSH to you device

    Code
    wget https://sky42.libreelec.tv/testing/hdmi-switch.tar.gz
tar -xvf hdmi-switch.tar.gz
# try e.g.
hdmi-switch/bin/switch-23-50-60.sh

    If you now put that on a button on your remote you can fix this pretty fast every time you need. As example for a BT Keyboard long press F5 as config in a keyboard.xml.

    Code
    <keymap>
    <global>
        <keyboard>
            <f5 mod="longpress">System.Exec(/storage/hdmi-switch/bin/switch-23-50-60.sh)</f5>
        </keyboard>
    </global>
</keymap>
    Quote from zitko

    I had the exact same problem as described in the first post. My setup is Pi 5 8GB connected to Denon AVR X2800HDAB connected to Sony Bravia XR55A80L. If the Pi source was selected/active on Denon while booting up Pi everything worked fine. As soon as I changed the source on Denon and then tried to get back to Pi I would not get video (No signal) in 50+% cases. Audio, on the other hand, worked (I could hear UI sounds).

    That was the case as long as I had Pi connected to CBL/SAT or Media Player HDMI input on Denon. Moving Pi to AUX1 or AUX2 HDMI input (two of three 8K ports on Denon), for some reason, solved the issue. Switching to Pi source now works flawlessly.

    I'm running Pi at 3840x2160, 60Hz with this added to the cmdline.txt:

    Code
    video=HDMI-A-1:3840x2160M@60D,margin_left=0,margin_right=0,margin_top=0,margin_bottom=0

    In addition to that, I added the following to the config.txt:

    Code
    hdmi_force_hotplug=1
disable_overscan=1

    I will try this, namely changing to one of the other inputs, I am using CBL/SAT.

    If that doesn’t do it I’ll add those hdmi hot plug and overscan lines to my config.

    If changing the input alone does this, I wonder what’s special about those on Denon AVRs.

    For info - I'm running my Pi 5 4GB into my Denon X2800H (non-DAB) and an LC C3 via an EZCOO remote controlled HDMI 2.1 (i.e. 48Gbs, not 18Gbs) switch connected to Aux 2 - one of the HDMI 2.1 ports and so far have no problems. I've not changed my config.txt file

    (Denon reduced the number of HDMI inputs on their newer AVRs so I'm having to upstream switch as I've run out)

    Quote from tomstephens89

    Switching to AUX2 on my Denon AVR-X3600H has not solved this problem.

    I have just added hdmi_force_hotplug=1 to config.txt and will see what that does.

    Is the AUX 2 input on your X3600H HDMI 2.1 or HDMI 2.0? (i.e. does it support 4K/120 and 8K/60?)

    (If all of the inputs on your X3600H are the same that would explain the lack of difference. My previous X2400H, which was HDMI 2.0a only - and limited to 4K/60 and no 8K - exhibited very odd behaviour with LE on a Pi 4B/5)

    Quote from zitko

    I'm running Pi at 3840x2160, 60Hz with this added to the cmdline.txt:

    Code
    video=HDMI-A-1:3840x2160M@60D,margin_left=0,margin_right=0,margin_top=0,margin_bottom=0

    In addition to that, I added the following to the config.txt:

    Code
    hdmi_force_hotplug=1
disable_overscan=1

    I tried that, but that didnt solved the problem on
    Pi4 + LE´´´ + X3800H + LG-OLED43C37LA
    Pi5 + LE + X3800H + LG-OLED83C37LA

    Staying on 3840x2160@30hz solved that Problem on every of the above situations. No lost Signals since then.
    Maybe its also the combination of newer LG-TVs + Denon-AVR...