Command block, sign, and book GUI pause the game, but not game music and sounds

The bug

In single-player, the command block, sign, and book GUIs pause the game, but not any music or sounds that are currently playing.

How to reproduce

1. Put a record in a jukebox
2. Jump and right click a command block
   → The game will pause (you will stay in mid-air), but the music will keep playing