I have multiple USB drives/ external hard drive. At first I found out that my 8Gig LACIE flash key was only able to carry about 6gigs, i was a little confused but I didn't care that much. But now I just found out that my Seagate 300gig external cannot add another 5.6 gig file when it has 60 gigs left. I don't understand what the problem is, and if there is anything I can do to fix that.