While the upcoming PS Vita will have cross-game voice chat on day one, many have wondered why the feature still hasn’t made its way to PS3, especially given how oft-requested it is. To that end, Sony has finally spoken out on why it’s not coming, pinning blame on a lack of available RAM.

Sony Worldwide Studios president Shuhei Yoshida tells Eurogamer it’s down to the way Sony designed the underlying firmware. Games eat up a bulk of the available 256MB of RAM, leaving very little reserved for the OS itself. And, once RAM is claimed by a game, it holds onto it forever — until shut down or exit.

“Once a game gets RAM we never give it back. It’s not possible to retrofit something like that after the fact.”

Presumably, changes could be made, but this would have a drastic effect on the PS3’s memory allocation routines. It’s a delicate matter as this in turn could break compatibility. Sony obviously can’t risk that at this stage.

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