Hoppers and droppers can put any item into a jukebox, even if that item isn't a record. As long as the jukebox is empty, or already contains that item hoppers and droppers are able to put (more of) that item in the jukebox.

Tapping the jukebox will make the it pop 1 of that item out and become empty again, regardless of how many items have been put in already.

Any item that isn't a record shouldn't be able to go into a jukebox.