What I expected to happen:
To have sound after changing the sound output device.
 
What actually happened:
All sounds have stopped.
 
Steps to reproduce:
1. Ensure that you are using the 'native' sound output device.
2. Ensure you can hear any Minecraft sound (music, jukebox, block, ...).
3. Change the sound output device.
4. Notice that that the sounds have stopped.
 
Steps to temporarily fix:
Restart Minecraft.
 
Remarks:
Switching back to the first output device doesn't work.
Was able to replicate this issue by using an external sound drive instead of the bluetooth headset.