Help ..Help.. Brother needs some help !!! with DVD screens

[Pitbull]

Hello ..
As I sit conteplating cutting a major artery, because I recently installed 2 xovision 2708 7inch sceens in the head rests. Bought a navigation bezel for another screen same model and size.
Everything was lovely until the 3rd screen was installed.I would get these vertical half inch lines every 10 minutes on all screens .I am using a video booster to beef up the signal.I was going to get this device to switch from playstation to or dvd to each monitor .But I got to get the screens right .The installer re -ran the ground ,mainline power in from the battery .One screen by itself look like HDTV,but when it is time share the signal,it is annoying to have a good pic distorted.Me and the installer are about to cut are wrists.Please help .
thanks in advance.David