looks like this game uses mono at3+ for the voice, you could try the program here that runs along side jpcsp, it requires "sound forge" though.
https://www.emunewz.net/forum/showthread.php?tid=5293
(the last post usually has the latest version.)
the only other known way would be to manually decode the audio on your psp.
https://www.emunewz.net/forum/showthread.php?tid=5293
(the last post usually has the latest version.)
the only other known way would be to manually decode the audio on your psp.
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