I hear a strange noise coming from under the car where the belt goes around?

It's possibly the alternator bearings which are on the spindle which routes the serpentine belt. Check and see if the alternator is securely bolted down since a lot of times it will make noise if it is not perfectly in line with the Serpentine belt. You may have to remove the belt and adjust the alternator which involves taking all the slack out of the Serpentine belt tensioner which can be tricky without the right tools. If you take the belt off be sure and make a diagram of how the belt goes around all the components cause it can be a major pain to find a diagram if it's not on a sticker under the hood.