The passenger side rear door on my superb sometimes fails to lock/unlock with the other 3 doors. It's an intermittent problem that only started happening about a month ago. I've had the car nearly 2 years and it's been fault free apart from this. Anyone have any ideas what I can check for before resorting to a dealer visit?

I'd be interested in an answer too, my Octavia estate does exactly the same - started a couple of days ago. Sometimes the other doors don't lock/unlock either.