ok, got the voices working.
It's not in the cpk.
It's simply some missing folders in the stream/voice/pc/us folder. After transferring the missing folders from the jpn game (and overwriting the rest to have everything jpn) the mute girl is now happily shouting and moaning in jpneverything else I left in english.
Are you running the game with full Japanese voice over? If so, can you describe how you accomplished it?
everything else I left in english.