Aust heads the SoundTrack_Cologne film music festival and conference, which he founded in 2004, as well as SoundTrack_Zurich since 2020. He has curated exhibitions, conferences, and music festivals, and was the Festival Director of Braunschweig International Film Festival 2014-2019. Aust has worked in the film industry for more than 25 years, with producer credits for 20 feature films and feature-length documentaries, including 101 Reykjavik, Stumbling Block, Parallax Sounds Chicago, Eva Hesse, and The Sound of Cologne. His directorial debut, CAN and Me, will hit cinemas in March 2023.

Aust is a voting member of the German Film Academy, Filmbüro NW, and the World Soundtrack Academy. He is on the Board of the MusicFilmFestivalNetwork, and of KulturNetzKöln. He is also the managing director, owner, and producer at TelevisorTroika GmbH, a Cologne-based company established in 1993 for film production, art events, and public relations in arts.