Human communication is fluid and observer-oriented

Language, music, visual art are all human communications. Their interpretation is completely human-centered.

This point is trivial, we have no reason to believe some random other species or type of being would assign any significance to a given musical piece.

The additional element that is interesting is that this means that among humans there is also a fluidity and inability to place objective meaning. The culture and person that interpretes any piece of communication will have its own context that will necessarily change the meaning and interpretation of that communication. See Music is culture specific.