What is the cracking sound?

Through the game, seemingly randomly a short cracking sound is heard during the game. What is it? Is it related to something?

Solution 1:

That may be the sound of glitches, like when the textures on the walls temporarily fade out. This seems to be the game's way of letting the player know that all is not what it seems.

Solution 2:

In my experience this sound always comes along with a graphical glitch: at some plays on the screen an interference appears and the worlds is changed a little bit for fraction of second. This is what Bryan Tsang already said.

And this supports the idea, which you can often see in terminals and in QR codes: Elohim is not really controls this world and may be he is not a god at all, but just wants you to think so. The same idea comes from quite odd behaviour of Elohim.