You will need to use a USB stick which has a bigger storage than 2GB! (Edit: Millenium confirmed that there is a current bug for using USB sticks, not all USB sticks will work and Millenium says this is not dependent on the storage size!). I advise you to use the Wave Editor Software. (please see the link section above). The Wave manager software will convert your drum samples automatically to mono and 44.1 khz. When you import samples via the 'loading direct from USB stick' technique, which are not in MONO, 44.1 kHz + 16 bit, they will be most likely played in a different tempo and pitch.