https://m.youtube.com/watch?v=alEHCvMHJPcPlay it. The existence of the object of sound is self evident.
All objects are equivalent, they are categorized in post processing by the mind. The actual contrast in the substance of each note in that tune is the same as between a musical note and a color, your mind is constructing categories and subdivisions when the sight you are seeing is as much a part of the music as the heard sound, and music as much a part of the seen sight, because sight and sound aren't ACTUALLY differentiated.
Further, there is no separate slice of existence possessed by an atom or the sound of this music. Just as the space in the room that you're in right now isn't a different space from what is outside of it. The walls create a sense of differentiation which simply is not there.
What consciousness itself is, is nothing. When things are not perceived, they are undifferentiated from that nothing. The same objects can be perceived differently, infinitely differently in fact, because their true nature is the same nothing.
Atoms aren't made of perception, and your perceptions are not made of an atom. In and out are concepts without ACTUAL difference. They occupt the exact same space. As such, sound being attached to a certain neuron pattern is obvious and easy to explain. It is only confusing if you make the false categorization that one is real, and the other is unreal. Both occupy the same plane of existence.
It is blatant if you just think about it. There isn't two existences, there is just existence. If anything is, from an atom to a sound to a sight to a black hole, it has to exist. It is simply existence. Everything is just existence itself. That's it.
