IF YOU ALSO EXPERIENCE THIS PROBLEM, PLEASE, GIVE IT A VOTE, AND IF YOU CAN, WRITE A COMMENT ABOUT WHAT YOU HEARD.

What I expected to happen was...:
Not to hear anything.

What actually happened was...:
There appears to play a high pitched sound, that is different when selecting Singleplayer, Multiplayer, Texture Pack, Options, and Language. It is always different.

Steps to Reproduce:
0. Make sure you are playing minecraft and "hearing" it through a cheap device, like your mobile's headphones.
1. Open Minecraft.
2. Click on any option.
3. You'll hear the high pitched sound, which can vary, depending on what option you clicked.

UPDATE/EDIT:
I can also hear it IN-GAME. If I look (i.e.) south i will hear a pitched sound, and if I head north, it will fade to another high pitched sound. But from what I hear, these sounds in-game, are really distorted, or "Bitcrushed" (see what i did there? The VST plugin effect? )