I'm kind of a novice here working on trying to get some settings right on my radio. For whatever the reason is, I can NOT get this radio to sound right. What I'm trying to do here is cut down on the amount of bass that go to my interior speakers, NOT my subwoofer setup. The issue I'm currently stuck with is that I can't hear my highs (voice, singing) while playing my radio. They get choppy and faint when it's up on the louder side. I have heard that tweaking the LPF/HPF (High/Low pass filters) may be of some help to me. As it stands they're are 6 UNLABELED hpf/lpf options on the radio, each starts with the letter "P" and followed by a number so it goes P1, P2, P3, P4, P5, and P6. Currently I've got it on P4, I have no idea if it's right. I just need some guidance from someone who's played with this particular head unit before. Please and thank you to whom ever responds!