Dell OptiPlex 745c (Early 2007) - Manual (Page 99)

Sound and Speaker Problems
Fill out the Diagnostics Checklist as you complete these checks.
No sound from speakers
No sound from headphones
CAUTION: Before you begin any of the procedures in this section, follow the safety instructions located in the Product Information Guide.
NOTE: The volume control in some MP3 players overrides the Windows volume setting. If you have been listening to MP3 songs, ensure that you did not
turn the player volume down or off.
Check the speaker cable connections — Ensure that the speakers are connected as shown on the setup diagram supplied with the
speakers. If you purchased an audio card, ensure that the speakers are connected to the card.
Ensure that the subwoofer and the speakers are turned on — See the setup diagram supplied with the speakers. If your speakers have
volume controls, adjust the volume, bass, or treble to eliminate distortion.
Adjust the Windows volume control — Click or double-click the speaker icon in the lower-right corner of your screen. Ensure that the
volume is turned up and that the sound is not muted.
Disconnect headphones from the headphone connector — Sound from the speakers is automatically disabled when headphones are
connected to the computer's front-panel headphone connector.
Test the electrical outlet — Ensure that the electrical outlet is working by testing it with another device, such as a lamp.
Enable digital mode — Your speakers do not work if the CD drive is operating in analog mode.
1. Click the Start button, click Control Panel, and then click Sounds, Speech, and Audio Devices.
2. Click Sounds and Audio Devices.
3. Click the Hardware tab.
4. Double-click the name of your CD drive.
5. Click the Properties tab
6. Check the Enable digital CD audio for this CD-ROM device box.
Eliminate possible interference — Turn off nearby fans, fluorescent lights, or halogen lamps to check for interference.
Run the speaker diagnostics
Reinstall the audio driver — See Reinstalling Drivers and Utilities .
Check the device option setting — Enter system setup (see Entering System Setup ) and ensure that the Audio Controller option is set to
On. Exit system setup and restart your computer.
If you have installed an audio card:
Enter system setup and ensure that Integrated Audio is set to Off.
Ensure that your speaker is connected to the audio card inputs
Run the Dell Diagnostics — See Dell Diagnostics .
Run the Audio Card Driver Diagnostics, If Applicable —
If you have installed an audio card, check your audio card documentation for details.
Check for software and hardware conflicts — See Reinstalling Drivers and Utilities .