TV out signal too bright/washed out

Hi there!

I am using a H3 board with TV out on a small 3.5" LCD screen (with composite->RGB24 IC). But I have a problem with picture being way too bright/washed out. The LCD luminosity can be modified with LCD-driving IC buttons, when set to lower value the picture gets better but colors are still too bright (even if luminosity is low)

I have tested the LCD with raspberry pi and output colors are normal.

I was wondering if there is a known reason for this and if it can be fixed? So far I have just found a topic about a raspberry pi HDMI output being too bright (https://www.raspberrypi.org/forums/viewtopic.php?f=28&t=50726) 

They suggest that a parameter "hdmi_pixel_encoding=2" in config.txt can help on raspberry pi for this issue. So I was wondering if they were some similar settings on armbian?

Thanks!

edit: I just had a suggestion of adding  a 50ohm resistor between AV and ground. I will test and feedback if it helps

2nd edit: I added a 50 ohm resistor and it worked. The thing was that my board was missing a small schematic at TV out. Most important was 50ohm resistor between AV and GND.

Same problem is on orange pi zero which don't have this schematic neither. If it can help some one some time.