Constant dying sound

In one of my minecraft worlds, the hurting/death sound effect is constantly looping really quick. I can not find any cause, since there are no mobs near the sound. I have even tried: /kill @e, but the sound is still here, how do i fix this? This is a forge mod by the way, but this really isn´t the mod´s fault, it does not alter the game, it just adds things. (making a new minecraft world and deleting this one would not be pleasant, since i have worked on this for a LONG time)