Mine does this too... they replaced the speakers and it still does it at certain frequencies. My guess isthe speaker mounting is vibrating due to poor design.
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2020 X3 M40i | Black | Current DD
2020 C8 Corvette | Z51 | Torch Red ... built and waiting for delivery
2016 M2 | Long Beach Blue | 6MT
2015 M4 | Austin Yellow | DCT
2012 MB C63AMG | 2011 E92 M3 | 2010 E92 M3
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