XPS L702X Internal microphone not working after installing Realtek HD audio driver

after installing the audio drivers from Realtek

Hello. Try the audio drivers from this Dell html page. There are 3 for win 7.

http://downloads.dell.com/published/pages/xps-l702x.html

First completely remove your current driver files the way you did when you installed the default controllers, or this way:

1. Open the Device Manager (Control Panel>Device Manager), and expand the Sound...Controllers category.
2. Right click on "Realtek High Definition Audio" to open the context menu.
3. Select to uninstall.
4. Put a check in the box "delete the driver software for this device".  Don't skip this step.
5. Restart the laptop. Windows will remove your current Realtek driver and its files and install the native audio driver.
6. But If you had any older Realtek driver files on the hard drive Windows will install the older Realtek driver. So go back to the Device Manager and see if there is another instance of Realtek High Definition Audio. If so, repeat the removal process and repeat as many times as necessary until there is no longer Realtek High Definition Audio in Device Manager.
After all Realtek driver files have been removed, you will see "High Definition Audio Device" in Device Manager. That is the name of the Windows native audio driver. 

At that point download and install the oldest Realtek driver from the html page. If you go from oldest to newest, you can skip the step of removing the driver files each time.

If the mic won't work with any of those Realtek drivers then I'm stumped.

First of all thanks for your answer jimco,

I meticulously tried everything you said but it doesn’t work no matter which of the 3 realtek audio drivers I install after clearing and rebooting.

I tried everything that crossed my mind but I’m hopeless. At this point I prefer to keep the High Definition Audio Device that windows installs automatically so at least I can use the microphone. For special occasions like when I use the laptop as Dj machine I can install the Realtek drivers for a while and uninstall them afterwards.

A couple of observations. With the windows native audio driver installed, when I go to Control Panel>Sound, in the tab record I find 2 devices, the internal microphone and the 3.5 mm connector. However with the realtek drivers installed, both are integrated in one device.

Another curios thing is that contrary to what you said, if I have installed the oldest realtek drivers, when installing a newer version the installer always forces the system to uninstall the older version first and reboot. After rebooting windows install the native controllers and it’s only then when I can install a newer version of realtek audio drivers.