A tech would try boards and connections, cables first. The cause here can't be nailed except by changing the parts. If there is any warranty, use it, If you can extend the warranty do that now.
I noticed today when I turn the TV on that a single horizontal line appears from the right side of the screen going left, but not all the way across. It sometimes appears in a different height, rarely at allhttp://i151.photobucket.com/albums/s143/kouichi341/lg%20problem_zps6xotn8vr.jpg, but always looks the same. After about 20-30 seconds, it goes away, but this is making me nervous. What is causing this, and am I going to pay out the nose to get it fixed?