The bug

Goat horns with any NBT data but without the instrument NBT data fails to play.

To reproduce

1. /give @p goat_horn
2. Rename the given goat horn using an anvil.

Expected result

The goat horn would still play.

Observed result

The goat horn no longer plays.

Original description

I named my Goat Horn using an anvil after that, I tried using it, but I can't blow it anymore. No sound comes out, nor does the animation for it work. It's just a useless object now.

Code analysis

Code analysis by apple502j can be found in this comment.