My Sony Bravia KLV-37S400A has a picture problem. Approximately 9inches (Lower screen) is covered with tracking (like an old video cassette would display) The service centre guy won't solve the problem but suggested to change the mother board itself & thats too costly.My Bravia is just 18months old. I know that the problem would be just a minor problem not requiring a change in Motherboard itself. Please help.