Enther this codes at song selection screen.

Code	Effect
DownLeft, DownRight, DownLeft, DownRight, DownLeft, DownRight	Command Options (Full Mode Only)
UpRight, UpLeft, UpRight, UpLeft, Center	Decrease Speed (all modes)
DownLeft, UpLeft, Center, UpRight, DownRight, UpRight, Center, Upleft, DownLeft	Full Mode (no USB)
UpLeft, UpRight, UpLeft, UpRight, Center	Increase Speed (all modes)