I got a 330i Touring with M-sport and also have this sound. The dealer can’t solve this and they say that I probably will have to live with it. They also told me that BMW says that this occures on both sedan and touring but only with M-sport chassi. I have two friends who have G20 2019 with M-sport but they don’t have this sound. Before I ordered my car this summer I test drived a G20 M-sport and it was very silent. This was one of the biggest reason I choose to buy my G21, because I of course, didn’t think that it would be any big difference in noiselevel between G20 and G21. It seemms to me that this occurs on cars that is 2020 model? Mine is produced in november I think. Probably almost all Touring, so they who claims that their cars doesn’t sound strange have probably bad hearing
If this is the new BMW standard I will never buy a BMW again