To Connect Audio Devices - HP OmniBook 2100 Reference Manual

To connect audio devices

Your OmniBook has a built-in microphone and two stereo speakers. The audio jacks
allow you to plug in external audio devices.
Plug a stereo input source (such as a CD player) into the input (left) jack.
Plug the microphone-into the microphone (middle) jack. The built-in
microphone turns off.
Plug devices such as headphones or external (amplified) speakers into the
output (right) jack. The built-in speakers turn off.
Making Connections
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