About 6 months ago, my 4+ year old 40" Samsung developed an intermittent thin red vertical line near the right edge. I can see I am not the only person to have discovered this issue. Tapping the screen or the bezel doesn't do much...certainly doesn't permanently fix it (and, amusingly, when I last tapped the top bezel I heard a piece of plastic or small screw drop inside the unit...oops!). Anyway, being of a generally pessimistic nature, I presumed this would be so expensive to repair (possibly requiring a new panel) that I didn't even call a technician; I saw a great deal on a new 46" TV, and the 40" Samsung is gonna be relocated to the recreation room (to replace 25+ year old Mitsubishi down there).
But just so I have closure on this issue -- Does anyone know what is the likely cause of this thin red line? Someone online described symptoms to mine, and an AV technician suggested it could be a "bonding problem" -- what is a "bonding problem?" If this is an easy and cheap-ish fix, I might take it to a technician, but since I have now replaced it as my main TV anyway, I am not willing to spend tons of cash to repair it. Is there anything I can try myself (besides tapping) that could have a meager shot at success?