- Press the “reset” button and turn the unit on again as soon as possible (if the instrument is switched on in 5 minutes your the track will be reconstructed and validated)

- May the USB partition is corrupted due some memory errors caused by a wrong device's removal from the PC when connected by the USB cable (unplug the device without safe removal procedure is ever wrong)

In this case, format the USB partition using the proper button on the setting page of the device.