I have a pair of Eclipse 3-way 6 1/2" speakers in my Nissan Altima, they are running off HU power. One of the speakers has this weird popping noise when the low freq. hit. I've looked at it and it appears that there is no obvious physicall damage to the speaker. I wired it on both sides of the car making sure the wires are connected correctly and it does the same thing when it is wired to either side. Does anyone know what my problem could be and how to fix it?