Check the format of the usb drives. Also you can try logging in to the console (ssh) and seeing the output of dmesg when you plug it in. I have a flashdrive and portable harddrive plugged in to my b1300 through a usb 3.0 hub and they work fine. A different usb harddrive i tried needed too much power and the usb port could not supply it so it did not work without a powered usb hub.