Ok so I own a Lexus ES300 and a few days ago I dropped a small rock (about the size of a dime) into the front A/C vent, the thin one that goes along the windshield which helps to defog it. I started driving a bit and I could hear the rock bouncing around and then very recently I have started hearing weird noises that sound like they are coming from the same area! Please help me how do I take it out? Do I have to take this to a Lexus mechanic? How much will it cost?