Hi gents, the sound doesn't particularly change on bends that I can tell. Just jacked each quarter and span the wheels by hand. Couldn't hear anything untoward over the usual slight brake drag. Checked all tyres, all pretty new although they were probably cheapest. No dishes or worn area. Wiggled the wheels and there was no sign of slack. Not catching anywhere. Would bearings be obvious under such a test?
I own a B8.5 S5 and I am hearing a hum/whir noise coming from the rear of the car (mostly on the right rear side). I had it checked by my local Audi indy mechanic and he says there is a barely noticeable noise but othing to be concerned about. He checked the wheel bearings upon my request but they all seem to be fine. In my mind, I am thinking that it may be related to rear diff noise or tire noise. Tires (Conti DWS06's) look great with lots of tread depth left. They do not have any signs of cupping or uneven wear.
This is not my first car with a rear diff and I remember hearing a similar hum/whirring sound from it as it went past a certain age.
The hum/whir noise in mine can be heard loudest at around 70 to 75-kph. Beyond that speed range, the noise level is much lower.
It was the the wheel hub... front near side (uk). Not only has the noise gone bit the whole car feels much sharper. I've had the car three months and was always disappointed with the way the steering and pick up felt. The problem bearing must have been affecting it even before it got noticeable grumble. Found a great idependsnt audi specialist who were able to diagnose and repair same day.