Laptop speakers won't play sound at all

Try running the audio tests in Dell Diagnostics. These interactive audio tests are designed to narrow down the problem to either the software or hardware. The tests are independent of Windows and drivers, meaning it doesn't matter if those are working correctly or not. To run Dell Diagnostics

1. Restart the computer and tap the f12 key as soon as it starts to boot up .
2. Select 'Diagnostic' from the boot menu. The computer will run its pre-boot assessment tests (PSA) before Dell Diagnostics starts. During the PSA you will hear some tones through the system speaker but this does not adequately test the audio hardware. Dell Diagnostics plays an instrumental piece of music complete with drums, so if you only hear some tones then you have only run the PSA.
3. Dell Diagnostics should open after the PSA tests, or you should see an option to open it. If you have ever reformatted your entire hard drive then Dell Diagnostics will no longer be there as an option. In that case run it from the Drivers and Utilities (Resource) CD if you have one.
4. Select 'Custom', then the audio tests. (At this point - after you have opened Dell Diagnostic custom - if you can't find the option to select the audio tests that is a symptom of a failed audio chip.)
5. The tests will run. Alternate between using headphones and listening to speakers in case only one signal path is working.
The tests will play some audio and ask you whether you heard it.
6. If you don't hear the music during the test it definitely means there is a hardware failure somewhere in the system. In this case Dell will repair the computer if it is still under warranty.
7.If you do hear the audio during the test but not when you boot back into Windows, that almost always means the hardware is okay but there is a problem with the audio driver or with Windows.
8. Error codes: If you answer 'no' to any question that the test asks you, the test generates an error code that can tell a Dell technician that you answered 'no' to that question. The test does not know the exact component that has gone bad. Before answering 'no' to a question, make note of the circumstances at that point so you will know in general what the error code means.

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If the terst passes then try reinstalling the Sigmatel HD audio driver. You can find it in the Audio category of the 1420 downloads page. I suggest for best results you do not use the Dell Download Manager, just download the normal way you would using your browser.

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If the problem persists after installing the driver you might have a problem with one of the headphone jacks when a computer has this combination of symptoms:

    * Speakers don't work and are not muted or deselected
    * Headphone jack does work
    * Reinstalling audio driver does not help
    * Audio test in Dell Diagnostics passes
    * On models with 2 headphone jacks, one may be "checked" in the control panel as if in use


The Dell laptops with 92HD audio utilize IDT's Universal Jacks technology, which is somewhat complicated. In addition to the usual mechanical parts, the jack also uses current & impedance-sensing techniques to trigger software configuration and switching (to send the audio signal to the speakers). So there are three areas of potential failure: mechanical, electronic, and software. Sometimes, a little very gentle wiggle of a plug in the jack will get it to resume normal functioning, at least temporarily. There is a sensing pin in the jack (Sense_A pin) that is used to detect the presence of plugs and it can be the cause of failure to trigger the software switching. Failure of the sense pin usually results in the computer behaving like there is always a plug in the jack.

Normally the audio test in Dell Diagnostics would confirm that there is a hardware problem, but the Universal Jacks can cause a false result in Diagnostics. That is because Diagnostics operates in DOS, outside of Windows, so a Windows software misconfiguration is irrelevant to the test even though in this case it is caused by hardware. So the audio test can pass in Diagnostics, correctly signaling that software configuration is the immediate cause of the problem, but missing that a hardware problem, the bad jack or sensing pin, is the root cause. In these instances the only reliable diagnostic procedures are to try a new motherboard or to use PC Restore (called Factory Image Restore in Vista) to restore the computer to its original configuration as shipped from the factory. If the speakers still don't work after PC/Factory Image Restore then there is definitely a hardware problem even if it passes the normally infallible Dell Diagnostic audio test.