Quote Originally Posted by DarrenW View Post

The chirp is still there.
As the tensioner gets older, it can wear on the bottom and the gap at the top starts to open up. This allows the pulleys to run on a slight angle pushing the belt across and causes the edge of the belt to chirp as it runs into the lip/edge on the next pulley. As it gets worse the edge of the belt will strip off too.

check your tensioner with a straightedge across the face of the pulley, and compare that to the other pulleys.

Explained pretty well HERE (better than I just did) and more detail.

Stevo