Sony PCG-VX88 VAIO User Manual page 75

To connect external speakers
1.
Verify that your speakers are designed for computer use.
2. Turn down the volume of the speakers.
3. Locate the Headphone
See the manual that came with your speakers for more information on its installation and use.
Connecting Speakers to the Headphone Jack
jack, and plug the speaker cable (not supplied) into this jack.
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