Mystery solved, well, sort of.
Amazon Fire TVs are currently unavailable due to "overwhelming customer demand," an Amazon spokeswoman said, after the little black box set social media abuzz when it mysteriously disappeared from stock on Amazon.com a few days ago.
For some users, the page says Fire TV could be available again by Aug. 23, which CNBC was unable to confirm. Amazon did not comment on a reason for the backlog.
The dearth of Amazon's $99 TV streaming device led some to speculate whether it was being upgraded to be 4K compatible, CNBC's Carl Quintanilla said on "Squawk Alley" Tuesday. A potential revamp by the e-commerce giant would allow customers streaming video on the web to get the highest image resolution on the market—four times that of an ordinary TV.