I can relate to these findings. I'm picky about my headphones. I'm picky about the audio settings on my sound system. If something is off, I'm quick to find fault with it. Bad sound annoys me. I can't enjoy a movie if the sound is off, and more than once I've tried to point out the defects to theater personnel only to watch them give me that "what?" look. I once got into it with the manager of a Cobb cinema over the sound in Team America: World Police. He couldn't hear the droopy wah wah of an imbalance in the projection reel, and then argued, "How come I can't hear it in the dialogue?" "The dialogue?" I gasped. "You idiot! How would you hear it in the dialogue? You have to hear the tone elongate for more than a second, dummy. Listen to the long notes!"
Yes, I almost got kicked out of the theater for using abusive language during a film in which one of the supporting characters explains the geopolitical differences between an anus, a phallus and a vagina.
That said, I was surprised when I tried to run A/B/C tests on the same track in 128, 256 and lossless formats - and couldn't honestly hear any. I wasn't surprised that my computer, running iTunes, showed no difference. Nor was I surprised when I got the same performance out of my iPod without an amp. Nor was I surprised when I got the same performance when I amp'd my iPod through the earphone jack. I was, indeed, surprised when I got the same sound using the LOD jack. Maybe my amps weren't good enough. Maybe it was the music I was listening to. I dunno.