Confirmed for Windows 10 Bedrock 1.16.100.
Affects 1.15.1 as well.
Affects Bedrock 1.12.0 on Xbox One.
Confirmed for 2.1.2494 on Windows 10.
Confirmed for 19w07a.
Confirmed for Windows 10.
Confirmed for 17w47b. Steps to reproduce:
1. After launching the game, open a world.
2. While the world is loading (preparing spawn area, etc.), press ESC.
Still present in 17w47a.
Confirmed for iOS version of Bedrock Edition. I placed a jukebox in my Creative World, inserted a music disc, and expected music to play. Instead there was silence, and the volume on my iPhone was almost maxed out.
EDIT: Disregard this comment, as I just found out that this bug report is a duplicate of MCPE-23761.
Confirmed for Bedrock Edition v1.2.1 on the Windows 10 platform.
Confirmed for 1.12.2-pre1.
Confirmed for MCPE 1.2 build 2, on Samsung Galaxy Tab A running Android 6.0.1.
Confirmed on Windows as well, for Preview 1.18.20.26.