I'm getting some rear video interference on the headrest monitor. Is there some type of power conditioner or capacitor I can use to cut out the interference. Picture is perfect when the engine is OFF. when engine is on I get some black horizontal line jumping around quickly on screen.

 

Avic D3 install in 2000 ML55. rear monitors are TKO 9" headrest monitors. everything works but the interference is a problem.

 

any pointers to solve the issue is greatly appreciated.