Please follow the procedure below to perform a factory reset on the Impulse.
1) Hold down the 'shift', '+' and '-' buttons then connect the USB cable to the Impulse.
2) You will now be in the boot menu. 'Exit' should be displayed on the LCD screen. Press the '+' button three times.
3) 'Fac Rst' should now be displayed on the screen. Push the 'Data' encoder three times.