XPS 8950, BIOS Sound Settings

There won't be any option to disable discrete graphics' audio output from BIOS settings.  It would be in Device Manager.

For example of an NVIDIA graphics card, open Device Manager=>  expand Sound, video and game controllers=>  right click on NVIDIA High Definition Audio=>  select Disable device

Thanks for your response Chino. I had already disabled the NVIDIA Audio in Device Manager. Unfortunately it has not solved my problem with being unable to electronically switch between Realtek outputs to Speakers and Headphones. This used to work, but occasionally, inexplicably, the ability to switch ceases to work and then I have to plug in the headphones only when I want to use headphones, then unplug them when I want to use speakers, all the while the System Sound Settings indicate Speakers are the output device, regardless of headphones plugged-in/out.

I see.  Assume you are connecting the headphones on the front audio port, with the system is on and running, if you disconnect and then reconnect the headphones, would there be a popup screen asking you to confirm the audio device?

Chino - Yes I am connecting the headphones to the front port with the system on and running. Previously, when the ability to electronically switch between speakers and headphones worked, I would get the popup asking what had just been connected. Now I don't get the popup when plugging in the headphones, yet the output does switch to headphones (while still indicating that speakers are the output device).

Check the Startup apps to be sure that the audio service was not disable.

Testing with the rear line out for speakers and the front port for headphones do get popup dialogue box for confirmation.  That is when you can switch output device by selecting volume, then select a sound output (on the right of volume slider).

Reinstall this Realtek audio driver if necessary.  Remember to click on the box for clean install (it will remove all previous installation).  Or perform uninstallation from Device Manager prior to reinstallation.

Thanks again Chino. I do have the same version of the Realtek audio driver installed as you linked ...

BUT good suggestion to check the Startup apps! I do have the Realtek HD Audio Services running. I also have the Waves MaxAudio Service Application running. This was the key! I ran the MaxxAudioPro app, and I saw that the Select Audio Device drop-down list and it still shows External Speakers only, even with the headphones plugged in ... but I also discovered that clicking on the gear icon in the upper right corner of the app brings up the Advanced Options checkboxes. There are only 2 checkboxes: [] Show pop-up dialog when device is connected and [] Activate Noise Guard. Both were unchecked. I checked the [] Show pop-up. Now I get the popup when plugging in the headphones. I specified over the ear headphones. Now I am able to use the system tray / quick settings to switch between speakers and headphones. I don't remember having to use the MaxxAudioPro app, previously, to enable electronic switching between speakers and headphones, but anyway I'm glad to find something that restores this capabi;ity.

I have the opposite problem. :)

I have made this complaint about not being able to disable the onboard Realtek audio for a while now.

I swore it used to be an option but I might be mistaken about that.

I suppose you have to deal with nVidia drivers to control that part of things, but it is much cleaner and doesn't interfere with onboard audio.

The XPS 8960 does have that onboard Realtek bios option so it's very odd the 8950 doesn't.

Since Dell is doing a terrible job as far as audio drivers/software, it would be nice if users like me who use NVidia HD audio to reap all the benefits of much more advanced codecs to eliminate having Windows get polluted with drivers we don't want or need even though we can disable in Device Manager after the fact.

Bottom line is that the Realtek drivers/settings are the real root problem, not nVidia.