Inqlude provides a comprehensive listing of all existing libraries for developers of applications using the Qt toolkit. Inqlude is run by the community and open for contributions.
OpenAl wrapper for Qt apps and games
neiasound is a Qt-style OpenAL wrapper for games. Not yet complete but already very useful. It is a clean, convenient api that can be plugged directly into your main loop. It comes with a (very primitive) .wav file reader, and includes stb_vorbis directly in the source tree. Also supports libsndfile.
There is also support for streaming dynamic playlists with intros and seamless looping.