Our 3CX uses a few Grandstream FXS/DECT set ups to work as Analog adapters for our analog phones. Slick set up and all is good. Until it comes to the firmware updates. I have no trouble with the HT802 or HT804 units. I was able to manually update the units with new firmware, and the 3CX system shows the unit provisioned with the updated firmware. The HT818 is updated on the unit, but the 3CX does not show as updated, or provisioned? Suggestions??