I was never able to play disc music this whole time [duplicate]

Solution 1:

How to Fix

You have not installed the free Music DLC from the marketplace. Go to the marketplace and just search up music and there is a free pack by Minecraft.

Reason

On pocket edition the music pack doesn't come with Minecraft, rather in a form of free DLC from the marketplace. You must download it from the marketplace. The reason it was not included was because they thought the amount of storage the game took up compared to the music was insane, so they decided to make the music optional as to not waste space some users may not have needed. This isn't as big of an issue now since most newer phones and iPads have a lot of storage, but that is why.