Need help with Body Kit Noises

I had the body kit professional painted and installed on my car about 4 years
ago, and now it makes creeking / squeeking noises when I hit a bump, get out of the car. The noises sound like when you are bending a long piece of hard plastic, and it seems to come from the side skirts. It makes that noise basically when even the car runs over any bumps, or when weight is added to it (like when someone sits in the car)....it's making the car sound worst then it is, since my car runs smoothly.

I need some suggestions on getting rid of the sound...cuz it is getting to the point that I want to take off the side skirts and put back the original side skirts.

Info
Car: Integra 95 4 Door
Body Kit: Racing Series 4PC Complete Kit with Type II Vented Air Dams
http://www.car-parts-accessory.com/WingWest.asp (link picture)