Unlikely to be a fault.
It's usually due to the DVD video output setting not matching the TV video input setting. ie. one in composite video while the other is set to SVHS, especially if used with a Panasonic TV.
If the DVD is connected to a Panasonic TV on AV2, press the green fastext button twice (while the DVD is playing in B/W).
AV2 on Panasonic TV is dual input socket capable of composite Video (AV2) or SVHS Video (AV2S).
Cobweb, July 2005