> Everytime a phonon backend does something 'new' that solves an existing problem - What happens then? You add API, and then all media players have backends that are subpar, or must media players verify if current backend supports the new feature?
The Phonon API is only about the basic stuff you find in 99% of apps: play a sound. So you don't need to change the Phonon API. The fact that the backend does something better (as is the case in GST 1.0, for example buffer sharing) does not mean you need to change the Phonon API to play/pause/stop a stream.