MSI MS-6199VA User Manual page 25

You can connect joystick or game pad to this connector.
Joystick/MIDI
Line Out is a connector for Speakers or Headphones. Line In is used for
external CD player, Tape layer, or other audio devices. Mic is a connector for
the microphones.
Line Out Line In Mic
1/8" Stereo Audio Connectors
NOTE: Line Out supports SPDIF converter. In case, you use the SPDIF
converter, change the output mode to digital on the audio setting.
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