In 1873 he followed the calling as a music teacher at the Präparandenanstalt (preparatory school) in Colmar, from 1876 at the Gymnasium and at the Höhere Töchterschule, a school for girls, in Saargemünd.
/JG 53 at the outbreak of World War II, Mix claimed 3 French Morane fighters over Saargemund on 21 September 1939, and four more on 22 November 1939 over Saarbrücken.