So after much research I know that I need a pair of headphones with at least an impedance of 60ohms to battle the constant hissing/mechanical sounds in the MacBook Pro. I've never bought a real pair of headphones before. Just in ear ones. I am leaning towards the Audio Technica ATH-M30's. Does anyone have any experience with them. Or can anyone recommend a pair that has at least 60ohms and under $100 on Amazon? They have great prices on headphones compared to Best Buy or the manufacturer. Thanks for your help! I'm going to be going on a trip soon and need to purchase in the next few days.