Users of gaming consoles experienced log-in problems on Christmas Day as a hacking group claimed it was behind the trouble.
Both Xbox and PlayStation said they were aware of users having difficulties logging in to use the online gaming services.
Playstation tweeted: “We’re aware that some users are having issues logging into PSN – engineers are investigating”, while Microsoft, which developed the Xbox, said: “Our team of engineers is moving to find a solution as quickly as possible.”
There was no official comment on the cause of the problems.
Twitter accounts under the name Lizard Squad asked followers to retweet or follow postings to get the services back online. At around 1am one account said “Attacks have stopped”, but later it claimed PlayStation was down again.
A number of users posted their frustration on social networking sites about the outage.
The latest trouble adds to Sony's woes after hackers calling themselves the Guardians of Peace, who are believed to have links to North Korea, broke into the company's internal systems and stole huge amounts of data last month.
The hack was reported to be in retaliation for the planned release of The Interview movie about a plot to kill North Korean leader Kim Jong-Un.
The movie was screened in America yesterday, having initially been cancelled amid threats of terrorist attacks on cinemas that chose to screen it.
The Sony leak resulted in the mass details of over 40,000 employees, full versions of movies yet to be screened and email exchanges criticising actress Angelina Jolie being released.
Following the hack, web security experts warned of the risks of similar breaches in future.