What is that whining noise I hear when accelerating?
If your vehicle makes a whining noise when you are accelerating, a transmission problem is most likely at fault. Whining when accelerating due to transmission problems can be caused by worn-out gears or low transmission fluid due to a leak. via
Why is My Audi making a rattling noise?
The most common reasons an Audi A4 Quattro has a rattling noise are the ball joints, struts or strut mount, or a problem with the sway bar links. via