My wife's r56 just developed what sounds like a wheel bearing going bad, but has no associated vibration that can be felt. It sounds like she has off road tires on the car as it gets over 30mph and starts making a constant drone. It's not too loud but definitely audible. It does not change with engine rpm or clutch in/out. I can put it in neutral at idle at 45mph and it makes the same noise. It does change in volume slightly going around turns, a little louder on left hand turns and quieter on right hand turns.

I jacked the car up and spun all 4 wheels and felt nothing, could not see any leaks in the cv boots or anything rubbing that could be causing it. Any ideas? I'm thinking maybe the intermediate shaft bearing?

 

What do your tires look like?

How old are they?

Runflats?

Miles on car?

 

Tires look fine, no cupping. They're not run flats, maybe 25k miles on them. They're due for a rotation so I'll do that and see if the sound moves. 133k miles on the car.