I have a 2006 bmw 330xi, there is kind of a scratchy noise coming from my speakers when I play songs with a lot of bass (the vocals are scratchy like, it's hard to explain). I have recently replaced my stock speakers with some 4" illusion electra's in the front with components in the back so I know it isn't a speaker problem. A guy a talked to said it may have something to do with the crossovers or something and he suggested getting a new amp maybe to power the speakers? Anybody else have this problem and know any way to fix this??? Please help, thank you! I know I do not have any blown speakers...}