Mine hums when coming to a stop, like 2-3-4 seconds. It also does this coming out of the driveway, going around corners, you get the idea. This is normal. I have a 2 year old compressor. I just have the rear air suspension.

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2018 BMW X5 Xdrive 50i (M Package)
2002 BMW X5 4.4i /w Sports Package (Sold)
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