Evil Voice is a proven myth in GTA IV.
Description
In GTA IV, it is a common occurrence of hearing the voice of a witch laughing. It is generally heard when the player is injured, especially by falling off a bike or ejection from wind shield, or by enemy fire. It can also be heard for a few seconds after getting hurt or killing someone.
Players have speculated that this may be due to some wrong sound file, though this theory is not confirmed yet.