Less XP then others!

Me and my friends are running the same stage on act 2, while he is getting 3,6 million XP an hour, im only getting 600k, we are only two levels appart, how is this possible. (We are clearing the stages in similar speed)

Read the wiki on Experience for more information, but you are subject to an experience penalty. Your character level is too high or too low for the zone level, and that is reducing your experience. For example, if you are level 20 and your friend is level 18, then you both receive full experience +/- 4 levels. The Crossroads has a zone level of 15. Your friend gets full experience, but because you are +5 levels, you are penalized. The penalty is greater the further away from the zone level you are.