The Artists

When you get in contact with the Empire of Artists, they send you a series of vocal transmissions. Why are they unable to communicate with the other Empires?

P.S. Our Galactic Nations contact has told us that some of your English puzzle answers will be useful here, but you will *not* need to use any translations of your puzzle answers. Additionally, it will be helpful to know as much of the language as possible through all of your artifacts.