In this design research the goal is to design a Sustainable HiFi Solution that the user can and are willing to use during their Audio Life. Context Listening to music in the domestic domain is something everyone does, but not all in the same way. In this research user of HiFi systems are the focus. HiFi Enthusiast listen to music to experience their Music. For decades HiFi systems were quite sustainable, put together out of separate components, if one failed only that one needs replacement. However things have changed, digital and analog systems are combined in one enclosure. Problem All-in-One HiFi solutions gain in popularity amongst Music Enthusiasts. All-in-One solutions are small, everything is contained in one enclosure. Easy to use, a mobile phone and application can be used to control the system. Analog and digital systems are put together to increase the use cases, however the technical lifetime of the different components is different. The digital parts can last for 5 to 10 years, the amplification part 10 to 20 years. A sustainable alternative needs to be designed, with the same benefits for the Music Enthusiast. Approach During this design research the double diamond approach is utilized. First to discover the current situation and fill in knowledge gaps using expert interviews and Hotspot Mapping. Thereafter online questionnaires and in-depth interviews provided the remaining data to start the design process. The design process is split in two, first the gathered data is used to design an overall ‘enclosure’, which is tested with the Music Enthusiast. Thereafter the technical implications of the design are researched, prototyped and implemented. Findings For the Sustainable HiFi solution to be saleable in traditional HiFi stores it has to be usable in a demo room. The HiFi solution should be adaptable to the changing needs and wishes of the Music Enthusiast during their Audio Life. By focusing on adaptability the sustainability aim can best be achieved via a new product design. For the Sustainable HiFi Solution to utilize its sustainable potential to the fullest different parts of the system should be designed using different circular design methods. In the new design unused functions should not be present in the system. Results The Critical Design Challenges for a Sustainable HiFi solution have been met. A modular design was made that can adapt to the Music Enthusiast wishes and needs with regards to Aesthetics, Functionality and Ease of Use. The different modules are easy to replace, without any tools, with the push of a button. The current status of the design is enough to clearly communicate the ideas and reasoning behind the concept. The next step would be to make a minimal viable product to demonstrate the potential of the IMS system to the Music Enthusiast.