I bought an 8GB Lexor Jumpdrive that has USB3.0 plastered all over it, but it is getting 10mb/s write and 32mb/s read in the disk drive test program from the App Store when plugged into my 2012 Macbook Air. When I plug it into a USB2 port on my Thunderbolt display, it's getting the same scores. Not sure if it's just broken, or what. Any ideas?