Wisps with newer visual models make the default human male "oof, aaah" noises when you are attacking them. They used to sound like wisps, until the models were changed some years ago on some wisps, but the new models were never given the appropriate sound effects. There are many examples, here is one in Morell's Castle, it sounds like you are attacking your next door neighbor rather than a wisp:
Here's another wisp model that makes human male noises instead of wisp noises, in Ruins of Lxanvom (Broken Mirror), Decay Decreased mission.
