rca tv composite rear plugs

i have an older 20 inch rca f19430  and the rear plugs composite plugs are not working properly , you plug any device and anytime it wants goes black screen and you touch the back or front plugs and the picture comes back.liked something its loose, but i open the case and i see nothing loose. can this pc  be change and ,what if the bad one its the front ? i know its an old tv, but im kind of broke right now to buy a new one, besides its only for the basement . thanks