Вероятно причина в загрузчике, вобщем делай по схеме, обновил загрузчик потом шить имиджем по новой
1. Unzip the Duo2_CFE_V2.zip to USB stick.(cfe_cfe_auto.bin, cfe_cfe_auto.md5sum and cfe_cfe_auto.model should be at /vuplus/duo2 folder)
2. Insert USB stick into the USB port of Duo2 and turn the power on.
3. Press the front power button when Update message is shown.
5. It takes just a few seconds to update.
5. If Duo2 displays the message "Finished..reboot", remove the USB stick and restart the box.
5. To update image later, you should delete the all cfe_cfe_auto.* at /vuplus/duo2 in USB stick once CFE update is finished.