What can cause a Squeal at about 2000rpm? on 2000 Oldsmobile Silhouette

We changed the both tenion pullies and the belt. The squeal went away for a while and now its back. Can't seem to find the problem. This squeal happens at about 2000rpms. It happens all the time and seems to get worse when its cold.

Asked by for the 2000 Oldsmobile Silhouette
Replace the tensioner assembly. Check alternator for bearing noise.