Digital preservation processes differ in detail depending on a variety of factors. Organizational matters such as retention periods or an overarching archiving mandate influence policies, which in return form the basis for preservation action. On a technical level preservation processes are directly influenced by the complexity of the material but also by the availability of tools to analyze and treat the material. All preservation action must furthermore be in-line with the intended usage of the material. The Goportis institutions preserve their digital holdings in a cooperatively operated digital preservation system. While the digital preservation system may be considered the technical framework of a preservation workflow for a specific collection, this workflow must be extended by format-specific tools and supported by a variety of institutional decisions and actions. The presentation will highlight challenges, strategies and approaches of a digital preservation workflow for non-textual materials using the example of AV-materials at TIB. It will show how requirements of a memory institution influence preservation decision and touch on state-of the art practises in digital preservation of AV materials.