Using The Audio-In (Microphone) Jack; Using The Audio-Out (Headphone) Jack - HP Pavilion DV4000 Hardware And Software Manual

Multimedia
You can also adjust volume by using the volume control software
available in the Windows operating system and in some Windows
multimedia applications.
The volume mute button on the notebook overrides all software
volume settings.
To access the Windows volume controls:
»
Select Start > Control Panel > Sounds, Speech, and Audio
Devices > Sounds and Audio Devices > Volume tab.

Using the Audio-In (Microphone) Jack

The audio-in (microphone) jack connects an optional stereo
microphone.
It is recommended that you use an electret condenser microphone
with a 3.5-mm plug. If you connect a dynamic microphone, the
recommended sensitivity may not be achieved.
Depending on your notebook model, the location of the audio-in
(microphone) jack varies.

Using the Audio-Out (Headphone) Jack

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WARNING: To reduce the risk of personal injury, adjust the volume
before putting on headphones.
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CAUTION: To prevent possible damage to an external device, do not
plug a monaural (single sound channel) plug into an audio-out jack.
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