Sony has told Eurogamer it is aware of a mysterious PlayStation 4 error which is affecting users' save files.
PS4 owners who experience the mysterious CE-34878-0 error have reported finding their saves corrupted for some of the platform's biggest games.
"We are aware of the cases and we appreciate your patience while we investigate," a Sony spokesperson told us.
The thread includes cases of users losing progress in an array of titles, such as Battlefield 4, FIFA 14, Call of Duty: Ghosts, NBA 2K14 and Assassin's Creed 4: Black Flag.
The spread of the issue - across multiple games and publishers - suggests its origin lies with Sony's hardware itself.
"Lost 40 hours of playing Assassin's Creed Black Flag," PSN forum member kickson123 complained. "Now I dont want to spend another 40h with possibility for same thing happened again. Also have PSN plus account and I was expecting that all my saves are 100% safe. At moment I am very disappointed in Sony."