To Connect An Audio Device - HP Compaq Presario,Presario 2100 Reference Manual

CAUTION
Series 2100 and N1050v
1 External microphone connector (pink)
2 Audio out (headphones) connector (green)
Note
Add-On Devices
Connecting External Devices

To connect an audio device

You can plug in an external microphone, external speakers, or headphones. In
addition, if you connect your notebook to the port replicator, you can plug in a stereo
source (such as a CD player) or a device that accepts digital audio (such as a digital
audio recorder).
The headphone and line-in jacks are three-terminal stereo jacks. They are not
compatible with two-terminal mono plugs. Connecting a mono plug into either
of these jacks may damage the notebook.
Attach the audio cable to the corresponding audio port on the notebook or port
replicator.
When you plug a device into the headphone port, the built-in speakers automatically
turn off. When you plug a device into either audio port on the notebook, any device
connected to the corresponding port on the port replicator is ignored.
50 Reference Guide
Series 2500
1 Audio out (headphones) connector (green)
2 External microphone connector (pink)