Hi
I had what sounds like the same noise from my
mc last year, the clunking noise came from the left front, the car went into the dealer ( Sytner Leicester) after several attempts to fix the problem they changed the gearbox ( Gertrag) Problem solved, they think the noise was coming from the diff section of the gearbox.
The noise started at about 4k the gearbox was finally replaced at 12k if you leave it it just gets louder.
DI 001