Here's an anecdote for everyone invested in quality audio:
This morning, for reasons I won't annoy you with, I saw an ear/nose/throat specialist for the first time in my life. As part of the exam, the doctor offered to clean my ears (though I wasn't there for a hearing problem). "Why not?" I answered, and doc proceeded with a quick, painless flush. He informed me afterwards that my right ear was, in the language of his specialty, "gunked up." Ewww!
Voila, when I returned home and switched on some music, I noticed immediately that the audio balance seemed much improved. Upgrade! And I hadn't spent a dollar (on audio equipment, that is).
Moral of story: No matter how much you spend, no matter how much you tweak, your system is only as good as your ears.