Sony PCG-GRX690K - Manual (Page 136)

Enabling the audio feature
If you do not hear sound when playing a CD or DVD, you may need to enable the audio feature.
To enable the audio feature
1. Click Start, Settings, Control Panel, and System. The System Properties window appears.
2. Select the Hardware tab, and click Device Manager. The Device Manager window appears.
3. Double-click the optical drive to open the sub menu.
4. Double-click the listed drive name, and click the Properties tab.
5. Click the Enable digital CD audio for this CD-ROM device check box if it is not already selected.
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