Every time I start my projector, the screen goes black. I have to reboot the LibreELEC with the smart phone app in order to get the picture back. I think the signal doesn't get lost, since I never get any sort of dialogue about lost signal. However, the screen remains black.
I have a Marantz AVR with two HDMI outputs (main and monitor). TV is attached to this main HDMI output and projector is attached to the monitor output). When I start the system, I can see the picture in TV fine. But right after projector starts and monitor HDMI output activates, the screen goes black. Projector is receiving a signal, otherwise it would show a dialog telling there's no HDMI signal.
What happens in the moment when the second HDMI activates? TV will be shut down a moment before the projector kicks in.
(edit: When running a Chromecast or Windows 10 the same way, there's no problem what so ever.
RPI4 2GB 16GB
TV LG Oled 4K 60Hz
Projector FullHD Optoma