Gamers have been facing connectivity issues with Xbox Live and Playstation online services.
Microsoft and Sony – the companies behind the consoles – have not given an explanation.
But a hacker group is claiming responsibility for the Christmas Day problems. “Lizard Squad” has not been reached for comment.
Microsoft and Sony expected heavy use as people who received console presents tried to hook up.
The problems may have been made worse by Sony’s decision to let consumers download the controversial film “The Interview” through Xbox Video and other online services.