A day-one firmware update is causing headaches for some new Wii U owners, according to reports circulating online. Consoles that lose power while the massive new system software is being downloaded and installed are reportedly being bricked.

L.A. Times reporter Ben Fritz is one of the most prominent people to tweet that his system was rendered useless by an interruption during the roughly 5GB download, which took over an hour to complete in our tests. Other users on Twitter and gaming forums around the Internet are reporting similar issues. While most users are reporting power interruptions as the cause of the bricked consoles, some reports suggest that losing an Internet connection during the download may cause similar problems.

Out of the box, the Wii U isn't useful for much more than playing games. The launch-day update is needed to activate system features ranging from the new Miiverse social network and online eShop to the ability to play older Wii games on the system.

Nintendo has yet to issue an official comment on the bricked consoles, but those new systems will still be covered by the company's standard 12-month warranty and should be freely replaced.