The jukebox can not be heard unless the camera is pointed towards it. If the player turns the camera, the volume quickly decreases then becomes silent when the juke box is out of view. This does not seem to be affected by the players distance from the juke box. You can be standing right next to it and hear nothing, or you can be dozens of blocks away and hear it only if you are facing in it’s general direction. I logged into the same realm on my switch and it worked normally, I could hear the record regardless of the direction the camera was pointed.
This issue is being tracked at MCPE-172380.