It looks like the new version 18.104.22.168 software update has blocked the ability to root the Amazon Fire TV and Fire TV Stick using the KingRoot utility. I have not received the update myself to confirm it, but IanMoz has commented that he was unable to root his 1st-gen Fire TV with KingRoot 4.1 after updating to the new software version. If you want to root your Fire TV, or keep root, be sure you have software updates blocked on the device itself and remain on software version 5.0.5 or older. There is also a report that Fire TV software updates are now being distributed via SSL. I have not confirmed this yet, but if true, it means blocking updates via your router or OpenDNS will no longer work. I will update this post once I receive the update and can confirm this information myself.