Since you're not getting sound from any source, I think the problem must lie with you sound settings, your sound card or your speakers.
To narrow this down:
Speakers first
Verify that you're getting a power light on your speakers, if your speakers require external electric power (called enhanced speakers, which most are now days).
Depending upon the speaker this could be displayed in variety of ways.
Volume control can be set (or mis-set) in several places:
1. On the speakers themselves
2. On multi-media keyboards (volume up-down, Mute)
3. By clicking the speaker icon in the system tray (by the time display, lower right-hand corner of the screen)
4. Or by double clicking on the speaker icon,
5. Or by going into the Start Button/Control Panel/Sounds and Audio Device (Classic View - in Category View it is called Sounds, speech, and Audio Devices). Windows XP
6. Check if any thing has a "Mute" check. If so, uncheck that and try your audio again.
If all volume controls and mute swithes are set correctly, there could be a fault with the sound card. Because you had the case open to install the CD-DVD drive it is possible that the sound card came loose. I would recommend opening the case again and checking that the card is properly seated. Be sure to follow all safety instructions and Anti-static procedures. I suggest removing the card, then reinserting it.
Check the sound system in the DXDIAG tool.
1. click Start
2. Click Run
3. Type in: dxdiag
4. Click Run,
In the DXDIAG Utility5. OK the WHQL dialog box
6. Choose the Sound option.
7. Check for any "problem files" and note them and let us know.
8. Run the sound tests. Any thing fail?
9. If so, click on the More Help tab and follow those steps.
Note-if you don't see a "Run" command:
A. Right click on the Taskbar
B. Choose Propties
C. Click the Start Menu tab
D. Customize Button
E. Advanced tab
F. Scroll down to and check the Run command option
G. OK your setting selections
If the DXDIAG doesn't help, you can uninstall then reinstall the software drivers and see if that corrects the problem.
(Windows XP Procedure)
1. Right click on the My Computer" icon and choose Properties
2. In the System Properties Window, click the Hardware tab.
3. Click the Device Manager tab
4. Click the + sign to the left of the Sound, Video, and Game Controllers.
5. Right click on your audio card and choose Uninstall
See this picture 6. Restart your computer. The audio card will be reinstalled during the startup, assuming that the card is properlly plugged in and in working order.
I hope something here will cure the problem. If everything was working before you changed the CD-DVD drive, I would guess that the problem is something simple, but these can often be hard to find. If this doesn't correct the problem, please let us know.
Dwight