BMW actually acknowledge there are "acoustic abnormalities" with the steering rack and having undergone around 14 part number changes they now sell a repair kit for ~£20
Scroll to the bottom of this link...
https://www.etkbmw.com/bmw/EN/search...0d/ECE/32_2071
The real cheek is that they arent doing a technical recall when they practically acknowledge there is a defect!!