Does anybody know why the sound of my system fades in and out as far as the "highs" go. My sound quality will be very good and then all of a sudden it fades out as if the treble were turned down. It cuts in and out like this and the sound is bad when it does. It's just muffled sounding and I like high treble. My headunit is newer and my speakers are newer as well. As a matter of fact I replaced the stock speakers with new Polk audio speakers thinking that may solve the problem but it didn't.