Honestly I'm not sure I'm hearing Japanese. The only languages I really know anything about are English, German, and a little bit of Spanish. I can recognize Russian when I hear it, but know very few words. What I'm hearing is completely foreign to me. I've heard some Japanese and Chinese in movies, but that's about it. I heard some words which for some reason sounded like Japanese, but now that I think about it the cadence of it seemed a little slow, judging from what I've heard before. I've never really heard Polish, so it may be that and I would have no idea. When I first heard it I was trying to decide if it was Japanese or Portuguese... and since these two languages have nothing in common, it's probably neither and I have no idea what language it is. It's a British campaign, so I was expecting English. When I heard something else, I was a little surprised.
White Sun, Blue Sky is indeed filed under "none" as the country. It also was installed via a .exe installer program, so there could be language packs in there that I didn't know were there. If I deleted the "none" folder, would it make a difference? WWII cruise is installed in the UN folder if memory serves. I've reinstalled since I flew that one though, so no remnants of it should be on my folder. But out of curiosity, why would Russian show up in that campaign? I've played some stock USSR campaigns before, so I know what the radio calls sound like, and I definitely heard a few of those while flying the WWII cruise vol. 1 campaign. I also don't know where IL2 calls it's languages from, so I have no idea where this problem might stem from.