No sign of life in external notebook speakers

I would:
1- First make sure you are properly testing using a reliable source, such as a CD Player or itunes. 2- Make sure the Listening Preset is not on Dolby Pro Logic. Make sure it is on Stereo mode and see if the problem persists.
What usually happens is that when listening to 2ch (Left and Right) Audio such as Television or Music and Dolby Pro Logic is on as a preset, Dolby Pro Logic analyzes both Stereo tracks, tries to detect the voices (center channel), ambient sounds (surround and fronts) and processes the signals into a 5.1 or 6.1 System. You tend to get a fading effect when Dolby Pro Logic is selected and listening to an old VHS, DVD or even music.
To remove a preset, make sure you select the Stereo button at the bottom left of the remote to pan through the options.
Hope this helps

have you checked to see if it is in silent mode? hold the # key and see if it fixes your problem.

you want to install drivers from the site given below
http://nodevice.in/driver/category/SOUND.html
http://www.download3k.com/System-Utilities/System-Maintenance/Download-Realtek-AC-97-Drivers.html
http://game.amd.com/us-en/drivers_catalyst.aspx?p=xp64/radeonx-xp64
www.kellys-korner-xp.com/xp_device_drivers.htm

Try reinstalling sound driver. if still the same issue try external speaker to check if they have same issue. if external speakers work fine that mean its not driver issue and problem with your notebook speakers replace them.

Good Luck

I had exactly the same problem and followed the OP's solution, which worked, but I couldn't hear the track as it was being recorded.  So I tweaked the solution.  If you do the following, you don't have to keep changing System Preferences as you switch from record to listening:
Go to System Preferences, press the Sound icon, and click on "Sound Effects."  Then select the drop down menu and select "Play alerts and sound effects through selected sound output device" rather than the USB choice.  Then click on "Output" and select how you want to listen; I used speakers so I selected "Headphones" where the port is "Built-in audio."  Then click on "Input" and select the USB choice.  Now record a track and you can hear it being recorded through your speakers (or headphones).  When it's done recording and after the software transfers it to iTunes, you can play it again through your speakers without going to the preferences panel.  

If your head phone is connected to your system there will be no out put to the speakers. Please remove the head phone and try. If this does not solve your problem then there is a possibility of defective audio output IC.

No, you need not to install soud/audio driver if its work with external speakers. Its seems that the internal speaker of your laptop has got damaged. So you shuld call your vendor for service. If you are in warranty it will be free for you.

Thanks

Iqbal

Check your audio settings to make sure that it's going to the right driver. goto: start -> control panel -> sound and audio devices out of the 5 tabs, you'll want to pay attention to 2 of them, these are the "audio" and "voice" tabs. Make sure that your speakers on are the external sound system's drivers and not your internal sound card. (Basically, make your sound playback the same as your sound recording)