Linux Show Player, LiSP for short, is a free cue player, mainly intended for sound-playback in stage productions, the goal is to provide a complete playback software for musical plays, theater shows and similar.
Here some functionality offered by LiSP:
Cart layout (buttons) for touchscreens
Concurrent cues playback
Realtime sound effects: equalization, pitch shift, speed control, compression
Peak and ReplayGain normalization
Send/Receive MIDI and OSC
Can play (almost) any kind of media file
Currently, only GNU/Linux systems are supported.
The application is quite stable, is already been used for multiple performances by different people, but, due to the heterogeneous nature of the GNU/Linux ecosystem, my suggestion is to test it in a “production” environment to detect possible problems with some configuration.