This random noise sound happens expectationally, no idea what it triggers.

I noticed this sound triggering once in a while since version 1.8 but never though anything of it because I couldn't find other hearing it. After doing some research I found it in a few YouTube video's of minecraft as well.

My first instinct was, is this some sort of cryptic easter egg? Well my tries resulted in nothing. So I'm not sure if this is a bug or an easter egg. I attached the noise.