Meson-current framebuffer showing wrong colors with certain HDMI adapters/displays

I am experiencing some problems with HDMI wrong colors. It happens on all meson boards I tested (lepotato, c2, and a custom build for Khadas Vim2).

It only happens with certain monitors/HDMI adapters, others work fine. In addition, I cannot select other resolution than the default (in this case 1280x720).

I think the problem must be in u-boot hdmi initialization, because it is also present during the armbian boot logo. The problem happens in framebuffer console, Armbian boot logo, and X session with fbdev driver.

These are some screenshots of the failing displays: https://imgur.com/a/fW7lskz

This is something similar to what is reported for Odroid C2 in HK's images: https://wiki.odroid.com/odroid-c2/troubleshooting/forcergb , I am not sure if it is related.