After changing out the serpentine belt, I noticed some belt whine. Not really noticing what it is, I had the pulley on the tensioner replaced and the pulley after the alternator replaced. I also had a new alternator thrown in just to make sure the problem was fixed. And, nope. still the belt whine. It was when the mechanic showed me (not a dealer mechanic) that the belt was actually rubbing on the tensioner arm a little bit and that is what is making the whining sound. I am open to suggestions as to how to fix this issue. Longer / shorter belt? Grind a bit of metal off of the tensioner arm? It is driving me nuts. It is a bit had to see in the picture, but, the belt is rubbing ever so slightly on the tensioner.