Make sure you have the box “Delete the driver software for this device” selected and click OK. Once you do, go ahead and right click it and select “Uninstall device”. Once you’re there, scroll down to “Sound, video and game controllers” and find “Realtek High Definition Audio”. To do this, go to the Device Manager by either right clicking the start button or typing “device manager” into the start menu. This might seem counterintuitive, but before you go looking to reinstall the Realtek HD Audio Codec driver, you’re going to have to uninstall all traces of your existing audio drivers.
