按照卡刷方法:
1. Get 'rootfs.bin' of firmware version 3.3.4. (use 7z to extract the firmware bin)
2. Copy 'rootfs.bin' to sdcard which is using FAT32 format.
3. Power Off G3.
4. Insert the sdcard to G3.
5. Press the front button of G3.
6. Power on G3.
7. Wait three seconds and release the button.
8. If the LED is turned to RED, it starts to flash 'rootfs.bin'.