A few players have reported sound issues with Bioshock 2. The volume on weapon sounds was much lower compared to the game, almost as if turned down. Unforunately, this wasn't fixed with the release of the Steamworks edition. A clever user on Steam figured out that an updated configuration file was causing the issue and replaced it with an earlier version of the file. I tried it out for myself and here are the results. The footage was taken with NVIDIA ShadowPlay and volume was not adjusted between game sessions. Hope this helps.
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