Dell Latitude E6410 audio out has stopped working

Hello. You can test by switching from the IDT driver to the Windows native audio driver.

1. Open the Device Manager.
2. Expand the "Sound, video & game controllers" and right click on "IDT High Definition Audio Codec".
3. Select to "Update Driver Software".
4. Click on "Browse my computer for driver software".
5. Click "Let me pick from a list of drivers on my computer".
6. Put a check in the box "Show compatible hardware" if not already checked.
7. In the list of devices, click "High Definition Audio" (the native driver).
8. Click "Next".
9. On the Update Driver Warning box, click "Yes" (install the driver).
10. Restart the laptop if prompted. If not prompted, sometimes you have to restart, sometimes not.

[To get back to the IDT driver, do it again but reverse the names in steps 2 and 7.]

If you have the same symptoms with both the IDT driver and the native driver, then the hardware has failed and probably need to replace the jack circuit board, or alternately you could use a usb audio jack.

Thanks for the info, I did all the processes but still silence. I don't think the jack socket is broken as I haven't used it since the last time it worked. I am sure it must me a software issue. Is there another driver that can be used/tested ?

I did all the processes

If that means that you installed the Windows native audio driver (listed in Device Manager as High Definition Audio Device) and the headphone jack still did not work, then it is most likely hardware failure, either in the computer or the headphones.

The reasoning behind it is that it is astronomically improbable that both drivers, which are from different manufacturers, would each separately develop the same odd bug at the same time, out of the blue.  I say "odd" because your model doesn't have a lot of software interference with the headphone jack as do more recent models with Realtek audio. In those cases there can be constant problems getting the jack to work properly. It's easy for a Realtek driver to mess with the jack, but not for an IDT driver or the native driver.

Is there another driver that can be used/tested

Dell had released 4 IDT drivers for the Latitude E6410 running Win7.You said you downloaded the latest, which was released in September 2010. If that replaced an even older one, then you have already tried 2 out of the 4. You can get the other 2 here. Before installing an older IDT driver, you should first completely remove the current IDT driver. Do it in Device Manager and check the box to delete the driver software. If the current driver is the native driver, then don't remove it -- just install any IDT driver over it.

A real test, similar to to the test of installing the Windows native driver, would be to run Linux Live operating system off of a cd or flash drive, and use its native driver. If the same thing occurred in Linux Live, that would rule out problems in Windows, and in the IDT driver, and in the Windows native driver, which would leave hardware or firmware. The only firmware involved is the BIOS, so if you haven't changed it since the last time you used the jack, then it's the computer or headphone hardware.