I’m not interested in what you think of me
Of course he's interested in what people think of him. The defensiveness is obvious evidence of his insecurity and neediness. Unfortunately, I don't know how to really help him. I don't think he's hit bottom yet and he's definitely not going to admit that he has a problem. If I were him I would hope a friend would come over and rip out everything and make me listen to my system "naked". Sure, I'd probably puke me guts out for a few days as the tweaking cravings subside, but in the long run I'd be better off. Let's just hope he eventually finds the one true path to enjoying listening to music.
BTW, other than the tweaks I think he has a pretty nice system. I would like to hear more about the DAC.