Hi, and thanks for taking time to help with this possible problem. I have a 2000 Honda Accord 4cyl/2dr. I recently had installed a new exhaust and headers(4-2-1). As of 2-3 days ago i've noticed a decrease in sound from when it was first installed. When it was installed it sounded like a really good and now it sounds no differnt from just a muffler. Is this normal or a sign or something major?