Squeeling V belt and CVF alternator

It’s not going to help much but it could be the belt and a different belt and/or cleaning the pulley and belt might help? I didn’t have squealing from either my PS belt or alternator belt but replaced both since they had been on for quite a while. Thought preventative maintenance was a good idea (and belts aren’t expensive) considering I was going on a long drive. Bought new new Gates belts (same as the ones already on the car) and got a squealing when starting the car and getting it off the fast idle setting. Played with the tension of both but still had a squeal. First reinstalled the PS belt with the old one and still had the squeal. Played with the tension again of the alternator belt and still had the squeal. So then reinstalled the old alternator belt and the squeal was gone.