I have a jvc ksh99 head unit, infinity kappa perfect 6.5 components and a kenwood 749 4x40 channel amp and when I turn up the volume I get a bad hiss or shh sound whenever someone sings any S sounds. Whats the problem? These components were expensive so I dont think its them. Could it be my amp? I have it bridged so i think its like 120x2. I also set the jumpers on the crossovers so the tweeters are -4 db. Any help would be appreciated. thanks