Hello, I have had a similar problem with a waveshare 5" knockoff display on my orange pi 5.
I started to build the kernel so I could make changes to the hdmi driver in an attempt to make the display work. I make a clean build without any changes just to make sure that the pi would be able to install the kernel and everything.
To my surprise, when I rebooted after installing that build of the kernel the display just started working.
I am assuming that the kernel that was compiled is a newer version than the one armbian has released and someone else made a change to the hdmi driver to fix this issue. (I was very surprised and happy when it started working)
You can look into building the kernel yourself, but I will also supply the .deb (links below) that I installed that fixed this issue for me!
to install this .deb file, first download it and then run the command: sudo dpkg -i FILENAME
Google Drive: https://drive.google.com/file/d/1RFAC6DlSqPcIHc4bpZtY6kB_k9sXl-Ho/view?usp=share_link
Media Fire: https://www.mediafire.com/file/79nctsr6e8dbyeh/linux-image-legacy-rockchip-rk3588_23.05.0-trunk--5.10.110-S6547-D3037-P0000-C6cddHfe66-HK01ba-Vc222-B1666_arm64.deb/file
Hopefully this helps some of you guys out!
