First of all, since you said your device is OS 2.0, make sure you uploaded the correct firmware. Firmwares for hardware version 2.0 are available here:
http://raysfiles.com/os_compiled_firmware/legacy_os/v2.0/
If you are sure you used the correct firmware file, and you suspect firmware 2.1.7 is causing the NTP problem (which I am not aware), why not try to flash it back to your original firmware 2.0.4, it’s available in the folder. You can flash the controller to any version of firmware.