Joel Hernandez Fernandez

I can confirm that the achievement is not working in Windows 10 edition. I already try to get the achievement in different Meadow biomes and in different worlds. 
I also try to close the game and restart PC and the achievement doesn't pop up. I was trying to get all achievements and most of them work right away, but "Sound of Music" just don't pop up no matter what I try. Here is just an attempt to get the achievement. The disc used was "cat".

Hey Brenden, this issue was on Minecraft Realms? I can confirm that this issue exists since a friend and I also try to create a mob farm using a zombie spawner. After a while the spawner stop working. Minecraft Windows 10 Edition in a Minecraft Realms.