Hi, sorry for my bad english, but I'm not a native speaker. Recently i bought a faulty GBA. It's in bad condition but it runs games and sound is ok. Only problem is screen. When GBA is turned on colors are inverted, like negative picture, at first I thought it's something with screen, but when tested with other screen nothing changed, colors where still inverted. I'm afraid it's something with mainboard but I can't localize problem. Below is picture showing what is wrong: Any ideas what can I do to fix it?