power supply question

here i have this small portable digital video system with a small screen in the front (to view what you are recording) and a built in camera, it also has the ability to hook up to a computer. Lately while recording video the image in the small screen in the front begins to dim and sorta of flicker, i changed the power supplied and it fixed the problem for a week then it comes back, i want to continue troubleshooting before getting rid of it, any suggestions? i would appreciate the help.

It might have been a waste to replace the power supply. Sounds like faulty or loose wiring.