Judder

Has anyone experienced a judder in their mk4 polo auto? Mine is a 1.4 petrol.

Hard to describe, observed when stationery in queuing traffic. It's like the car is being given a little nudge. Feels like perhaps the transmission is catching more on one part than another, but disappears again when moving off. Or maybe nothing to do with the transmission at all as putting it into neutral I still observe some lumpiness. So some sort of misfire perhaps?

Just wondering if anyone else has experienced and what it turned out to be?

Or hints on how to investigate??

Thanks in anticipation