Scary Pop Up - Unknown Sound in clip

Scary Pop Up - Unknown Sound in clip is a screamer video uploaded to YouTube in May 2010 by user ThePopUpVideos.

Video
A box reading TRACK 4206# NOT PUBLISHED appears at the top before disappearing. Afterward, a clicking/crunching sound effect starts to play and the video states that a strange noise can be heard buried in the mix, with instructions to turn up the volume. After a while, it tells you to listen carefully, and at that very moment, a demon child from Dead Birds pops up with a scream from Mortal Kombat.

Link
NOTE: The following video contains a screamer.

youtube.com/watch?v=ND6xzsdbPIY