Ears of Amenasys

The Ears of Amenasys are a series of relics that started out in the possession of various Pactone tribes. When supplied with a small magical charge, an Ear will cause music to play from the item. The music is sometimes consistent depending on location, but there doesn't seem to be a rhyme or reason to the type of music that plays or the qualities of it. Not only can the music change per location, but it can also change depending on what's happening around it (perhaps reacting to the emotions of the people in the area).
Each Ear looks different, but they all appear to be carved out of natural materials. It is unknown how many there are in the world; they seem to be found in unexpected places with no sense of timing, and Pactones have been reluctant to share them with humans upon discovery recently.
The Ears of Amenasys provided the inspiration for the component of the Harmonic Servers that actually produces song magic to be heard in the world. That component essentially manifests the emulated emotional data into music.
All of this is to say, on a meta level, the Ears make what would be considered "background music" diegetic to the people in the world.

Mechanics & Inner Workings

The mechanics are an absolute mystery. There appears to be some kind of magic mineral core, but where the music is pulled from remains a topic of debate. Theories include drawing emotional energy from a shallow connection to the people around the core and, on a more farfetched level, playing the world's "heartsong" that is somehow endemic to the universe.

Significance

Cultural and scientifically significant. The existence of the Ears is part of the reason why music and expression through that medium are so vital to the people of Mixolys. As mentioned earlier, the mineral core also provided inspiration for a Harmonic Server component.

Rarity

Quite rare; the unpredictability of finding one doesn't help.