I have a 50" plasma TV and every now and then a straight line of green pixels appear from top to bottom. It tends to fix itself after maybe a week or two and then is fine for ages.

Anyone any idea what's causing this and if there's anything I can do to fix it?

Presumably it's a poor contact inside the PDP (Plasma Display Panel)?.

Cure would be to replace the panel (if it was even available), but that would cost more than a new TV.

It 'might' be possible to 'bodge' it by wedging something inside the set that holds the poor connection together.