Put the summary of the bug you're having here

What I expected to happen was...:
When I start a Music Disc and go to the nether and back I expected that the Jukebox was still playing and my parrot was still dancing to it.

What actually happened was...:
I put a music disc in a Jukebox. I went to the nether and immediately back again and it was not playing anymore, neither did my parrot dance anymore, even though it does not stop dancing when the song is over and I am near by.

Steps to Reproduce:
1. put a music disc in a Juckebox
2. unload the junks (for example by going in the nether and then immediately back again)
3. then the disc is no longer playing