That noise is most likely the idler pully. They have a roller skate bearing in them and all of them go away after a while.
the test is to take the belt off and attempt to wobble and turn the thing by hand if it is any tiny bit loose or you can fell the balls while turning it by hand it has went south and needs a replacement.. The squeal is sorta like a dinner bell...telling you it is time for getting off the couch..
The good part of it is the price..you will love how cheap a new one is.
Big JIm <img src="/forums/images/graemlins/pfft.gif" alt="" />

professional bovine relocation specialist