Samsung SP-L300 Owner's Instructions Manual page 24

Connecting an External Speaker
You can hear sound through an external speaker instead of the internal speaker embedded in the projector.
Prepare an audio cable (Not supplied) suitable for your external speaker.
Connect the [AUDIO OUT] terminal of the projector to the external speaker using an audio cable.
- When using an external speaker, the internal speaker does not operate but you can adjust the volume of the external
speaker using the Volume button of the projector (or remote control).
- The [AUDIO OUT] terminal can output all audio signals.