When I parked my X in the garage last week I heard a low volume mystery noise coming from the outside wheel well on the rear passenger's side. It sounded like a very low fan, or hum. I opened the back hatch and check the rear compartment above the wheel on the inside to double check that it wasn't coming from there. You could still slightly hear it inside, but it was certainly more pronounced outside. It lasted for at least a minute while I was there, and then I walked into my house only to return much later and it had ceased.

Any ideas what it is/was

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'14 X1 7000 miles

Hasta luego a

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