Hi, i have a 2011 macbook pro 15" 2.0ghz one. how can a computer that cost so much not be able to play 720p without a lagging every 15 seconds. i've checked everything on my mac theres over 2gb of ram free and plenty of hard disk space. i have tried with multiple 720p videos and they all have frame skips and work perfectly on my home pc. anything else i can try to improve videos on my mac?