I have this problem almost since I bought this car. On cold engine usually on 2 and 3 gear (very little on 4) I can hear strange sound and little car jerks. The problem mostly occurs when I drive on cold engine uphill around 2000 rpm's. It is hard to describe so I recorder video with this issue. You can hear it from 7 to 11 second and from 20 second for a while.

Golf - YouTube

What this can be? I already replaced a lot of parts and can't find the solution.

Another video from today on 2th gear and about 2000 rpms. You can clearly hear this strange sound from 30 second

Untitled - YouTube