Overhead dvd player was working fine then one day a problem..video plays on the screen but the sound is only crackle noise on both head sets. We have since tested another new headset and ruled them out as the problem. car electronic shop says it seems the repeater? is not sending the signal properly. they dont repair overhead dvd players. any ideas how to fix this possible problem?

Car Audio & Video - XO Vision - Wireless Infrared Stereo Headphones for Car Car Video Player