Ymuse
Ymuse is a simple, functional and fast GTK interface (client) for MPD. Free and open source program
Spotube
Spotube – lightweight Spotify client which handles playback manually, streams music using Youtube & no Spotify premium account is needed. Free cross-platform and open source software
AK Recorder
AK Recorder is a simple program for recording audio in Linux. Free and open source program
Amberol
Amberol is a simple music player. Free and open source program
Moosync
Moosync is a simple music player whose main purpose is to provide a clean and simple interface. Free and open source program
Kasts
Kasts is a program for listening to podcasts on a desktop computer and a mobile device. Free and open source program
Relaxator
Relaxator is a free and open source program for relaxing to the soothing sounds of nature
HBud
HBud is a free and open source simple music/video player and karaoke application
Qoobar
Qoobar is a free and open source, multiplatform program for editing tags in classical music files
Harmonoid
Harmonoid is a free and open source, cross-platform program for playing local and music from YouTube