The song in the video is Love Song: Ar-ra-rang 1 recorded on a wax cylinder in 1896 by American anthropologist Alice Fletcher, who requested its performance by three Korean students in Washington at the time. This was the first example in history of Korean traditional music being captured with a recording medium.
A wax cylinder is frail and sensitive to environmental conditions, and thus the sounds recorded on its wax surface tend to disappear into noise over time. The artist repeatedly uses a noise reduction plugin to keep the noise down from the song while gradually progressing toward the past.