The label Mille Plateaux focuses on concepts like virtuality, noise, machinism and digitality. In the most simple case, digital music simulates something that does not exist as a reality; it generates something new. It is the result of the teamwork of numerous authorities such as the 'musician', the programmer and the authority of the software program. Today, computer digital music can be seen as screen-based music, i.e. sounds become visible and images audible, but one can often forget that there is no mutual correspondence; and that this is simply a mechanism whereby a given program secretly directs the programmer towards significant ways of performing, creating apparently absolute relationships between image and sound. On the other hand, with the increasing complexity of software, the programmer loses insight into internal communication structures. Such complex programs are full of errors and can even act on their own initiative. Programmers and musicians who navigate through today's systems function as designers. But this is less a question of the design of a program's operation surfaces but of the programming of software and the navigation by its logic. One has to discuss the medial conditions of digital music, the more user-friendly the software, the less transparent is the medium itself; i.e. the more transparent the functions of a computer or a synthesizer (say, with the use of preset sounds), the stronger the medium proves to be non-transparent. Digital music is more about opening up given program structures; internal ramifications and program hierarchies are to be discovered.