I bought a portable USB 3.0 1.5TB Seagate GoFlex portable HDD to house my extensive movie collection when I bought my rMBP. The problem that I am running into now is that whenever I play movies off of the drive through iTunes, there is always a freeze and stutter every 6-12 minutes of the movie. It can be as long a second and a half or so each and makes movies extremely irritating to watch. Has anyone else had a similar problem or a solution to this? It seems to me that because I have so much RAM, iTunes could in theory move the whole movie over to the RAM and not have to access the disk, which I think is the problem. Unfortunately, it does not do this, as I think that this could be the perfect solution. Does anyone have any ideas?