Clicking noise from dash

when I unlock the door of the car with the fob and access the car I hear a rapid clicking noise coming from the dash from behind the radio area. It would be like a leaf hitting against something really quickly. It lasts for about 5 seconds and stops. When I start the car it clicks again for about 3-4 seconds and stops. Everything in the car is working fine and it starts fine but I am just wondering if its the start of something serious that would be better fixed now.