Have exactly the same noise on mine, also a 2018 car. I'm not sure I would have picked it up if I hadn't seen these posts but now it is very evident but only within 1st 1 to 2 mins of driving. Looking forward to update and I'll book it in with BMWHK to look at..
Tx
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F10 M5 retired
F90 M5 MBB & Silverstone...MSport exhaust and AWD = more happy screams from the kids per mile...Big Thumbs Up!
2018 SQ7
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