This sound happens if Kaspersky detected a virus. The first one is a loud pig squeal. The second one is a short and quiet chime sound.
Scare Factor Edit
HEART ATTACK for the first version. Unexpected viewers will definitely run away from this loud sound. We suggest that you must turn off your computer every night.
Low for the second version. It may still creep some, but it's the best and better than the last one.