We have a random problem where the car over revs on launch and the gear box clunks heavily.

We have been told this was fixed by a $2000 cable between the gear selector and the gear box, and that the problem does not exist by our VW service centre.

I need a legal way to record the Speedo to show the over rev and the clunk the car experiences. Any ideas?

Would a OBD device help me capture this also?

PS we have the DSG 2018 version.