I tried downgrading 3x times. 5.27.1 Did not work but the exact above combinations works."
Hardware/Software:
R7 2700x, Asus B450 Prime A, ASUS Dual RX6600
DE: KDE Plasma 5.27.10
OS: Garuda Linux x86_64
WM: KWin (Wayland)
Kernel: 6.6.8-zen1-1-zen
Probably the same as Bug 476375, based on the presence of the ddcutil downgrade. It looks like this occurs for some monitors and not others, based on ddcutil 2.0 now listing “invalid monitors” that were not listed by ddcutil 1.4.
Or perhaps something else that I missed, but the bug is long and full of pasted outputs.