No HDMI signal from Raspberry Pi 4 after turning TV & Soundbar off and back on

    I'm running LibreElec 9.2.1 on a Raspberry Pi 4, connected through a 4 port HDMI switch to a soundbar that's then connected to a Vizio PQ65-F1. When the TV/switch/soundbar are all on and I boot the RPi everything works great. The problem I'm running into is that when I turn them all off (except the RPi), then turn them all back on, the HDMI signal is lost.

    So far I've tried:

    • Add hdmi_force_hotplug=1 and hdmi_drive=2 to config.txt
    • Create an edid file
    • Disable CEC
    • ssh into the RPi and run "tvservice -p"

    The only thing that brings the signal back (outside of a reboot) is the tvservice command. Otherwise, nothing I've done seems to keep the HDMI signal alive. Obviously having to ssh in every time isn't an idea solution.

    Is this a known problem with the RPi 4? Or just something obvious I'm missing?

    TIA!

    Followup: After systematically removing components between the RPi and TV, I found out my issue is an HDMI switch that I'm using. Looks like this is less of a Kodi/LibreElec/RPi issue than it is a hardware problem upstream.

    I have a similar issue with one of my RPi4's which is connected to a long cable to a Onkyo amp and LG TV. Occasionally, with no apparent pattern I will switch it on to find a blank screen on TV saying no input. There is something coming from it as it would normally be a blue screen from the Onkyo amp.

    The amp always remains on or on standby however the TV is switched off via a smart plug.

    I've managed to figure out how to get the picture back up without restarting.

    tvservice -p

    systemctl restart kodi

    I'm not sure if I have to do a tvservice -o then -p in between the restart as yet.

    This is the dmesg log which could show something. I did try unplugging a couple of times, powering the amp off/on and Kodi crashed a couple of times too so who knows which is the error. I'll try get a more specific one next time.