From the writings of Aristotle [DeCaelo - 290b,12ff] ...
"It seems to some [ie: Pythagoreans] that bodies so great must inevitably produce a sound by their movement: even bodies on earth do so, although they are neither so great in bulk nor moving at so high a speed, and as for the sun and moon, and the stars, it is incredible that they should fail to produce a noise of surpassing loudness. Taking this as their hypothesis, and also that the speeds of the stars, judged by their distances, are in the ratio of the musical consonances, they affirm that the sound of the stars as they revolve is concordant.
To meet this difficulty that none of us is aware of this sound, they account for it by saying that the sound is with us right from birth and has thus no contrasting silence to show it up; for voice and silence are perceived by contrast to each other, and so all mankind is undergoing an experience like that of a coppersmith, who becomes by long habit indifferent to the din around him."