1999 Grand Am squeal

I have the most annoying squealing problem with this car. I have changed the serpentine belt twice and in both cases the squeal went away for a few days then came back. In the process I also changed the water pump, belt tensioner and an idler pulley but the squeal is still there. It gets worse as RPM increase. It is definitely a belt squeal and I have identified that the squeal is coming from the belt running on the upper ilder pully (near the Alternator). After everything is running hot for about 1/2 hr the squeal is no longer there. Any idea how to solve this? I know from the past that adding belt treatments can make the problem worse. I also thinking that maybe it has something to do with the engine mounts etc as the squeal gets louder when I rev the engine and it rotates but then again I am new at this. I was also thinking it might be the brand of belt (Torque=$40) but I bought it with a squeal 1 year ago and have changed the belt twice so that makes 3 different belts with the same problem? Any suggestions would be much appreciated.

OH also when I pulled of the idler pulley it did not fit snugly on the engine. There was allot of play there. Is this how they are or could the place where it sits be worn?

Thanks

It sounds like the bearings in the Idler pully are bad. Replace it with a new one and the squeal should go away. Usually the tensioner is the culprit but in your case the idler appears to be the problem.