Yeah with your guitar you're getting what we call fret buzz. It can be helped with a truss rod adjustmentand/or raising of the action(height of strings off the fret board). What your friend is reffering to is what is called intonation. When you tune your guitar check the same string at the 12th fret. If your intonation is good this should also be spot on. If it isn't when you play down the fret board it'll sound like it is out of tune.