Hi I am new to this forum and hopefully someone might have some advice. My daughters 2011 Mini first 90,000 km is making a strange hard to pinpoint noise that sounds like Whirr Whirr Whirr which is mainly noticeable on motorway doing 100 120kiph. as the car slows the noise slows. We checked wheel balance on all 4 wheels, have not checked wheel alignment. putting the car in neutral makes no difference, and there is no vibration.. Any ideas?