I have a 2007 1500 crew cab classic. I've notice the front left speaker has a fuzzy noise associated with bass. I have the stock stereo system. it almost sounds like something rattling from a distance but when you get really close to the speaker you can tell it's not something rattling but coming from the speaker itself. I've visualy inspected the speaker behind the panel and can't find anything wrong. Anyone know what would be causing this and how to fix it?