As is commonly the case after a new Fire TV model is released, Amazon is continuing to fix bugs and push out software for the new 3rd generation Amazon Fire TV. A new update with the same 126.96.36.199 version number but a new build number of NS6210/401 is currently rolling out to those devices.
It’s unknown what this new update changes, but it’s likely more bug fixes, like the NS6210/399 update before it. Amazon’s Fire TV Device Software Updates pages has been updated and now correctly lists 188.8.131.52 as the latest Fire TV3 software version, instead of incorrectly listing the latest software version to be 184.108.40.206, like it previously stated. Oddly, the software update build value is now listed as (0000033657220), which still does not match the NS6210/401 build value displayed by the Fire TV 3 interface.
Whatever the reason for the mismatched build numbers is, Amazon still only says “this software update includes general improvements and bug fixes” without listing any specifics about what has changed. If you notice anything new or different with this latest update, please mention it in the comments below.