No Sound?

OEM audio driver will need reinstall after every WIN10 feature update.

http://downloads.dell.com/published/pages/optiplex-790.html

Weird.

The drivers that windows automatically installs have always worked OK on my 790. I have had win 10 update to versions 1809, 1903, 1909.

I have a similar setup as the OP. with logitech speaker system plugged into the rear speaker socket. It has two small speakers and a subwoofer which also contains the amps, etc.

Maybe I'm just lucky?

You arent lucky.  Realtek Audio, Intel Audio, Intel video, Nvidia Video, ATI video, Realtek , INTEL, Broadcomm, Atheros WIFI and Bluetooth Drivers, etc are routinely and deliberately DISABLED by microsoft during feature updates.

Thats why people had it working initially and then it somehow got broken after a feature update.

The latest spat is with Bluetooth drivers and the KNOB vunerability.

The Realtek Audio manager app still appears in C:\Program Files\Realtek\Audio\HDA showing the RAVbg64 application, but when you run it (administrator or otherwise) it simply fails to work.

Some older drivers also need DOTNET 3.5 and compatability mode to work.

https://www.microsoft.com/en-us/download/details.aspx?id=25150

https://support.microsoft.com/en-us/help/15078/windows-10-make-older-apps-or-programs-compatible#1TC=windows-7

The safeguard hold was added by Microsoft in May 2019 after acknowledging an issue where computers with Realtek Bluetooth radios experienced problems when discovering and connecting to Bluetooth devices after installing or updating to Windows 10, version 1903 due to outdated drivers.

The settings for the ports are disabled and or missing when the OEM driver is disabled.

realtek settings

I'm confused then. Why is my audio still working fine through 3 windows feature updates, when they should have been clobbered every time?

I call that good luck.

Realtek drivers just like Intel HD drivers are not one ring to rule them all one driver for all models.

There are different versions of chip and driver for different models.

There is not a unified single driver that works with every realtek audio or usb or bluetooth or card reader etc.

The same is true with INTEL HD graphics.

The same is true with NVIDIA, ATI, Quallcomm, Atheros.

And when hardware changes from mainstream to legacy it gets worse not better because the current and up to date driver doesnt support the older legacy chipsets.  Luck has nothing to do with that.

You can't say everyone will have the same experience even with the same models due to other factors like corruption and hard drive dying and microsoft changing updates to revised versions.

@speedstep 

Your post seems to say that I AM lucky; very lucky indeed 

I'm Lucky to have _exactly_ all the specific minutia that allow the extremely rare circumstance of my particular installation of windows 10 NOT clobbering my 790 sound.

Well, right now, windows update is downloading the latest feature update (version 2004). So maybe my luck will have finally run out. I hope not.

I'll select an appropriate title from my meager music CD collection to test it with, and let you know how it goes

Well the latest window 10 feature update finished (version 2004).

I cautiously  tried the sound out to see if it got clobbered as you said it would.

I chose Elton John's album "The big Picture".

Not his best work, but Speedstep, you really need to get hold of a copy. Listen to it, and let the lyrics sink in. If you understand it at all, it would help you a lot!

I'm listening to it right now. Windows  update  to 2004 didn't wipe out my sound.

I guess I'm lucky.

Yes, random and unpredictable. When you don't get affected, it's called "LUCK".

@donm4599x,

If you want check out a couple of articles...  Also, from what I read previously, Win10 updates breaking things seems to depend on PC and doesn't necessarily go across the board.  Sometimes, it even depends on certain apps/programs.

https://www.google.com/amp/s/www.forbes.com/sites/gordonkelly/2020/05/24/microsoft-issues-windows-10-update-warning-kb4556799-free-windows-10-upgrade/amp/ 

OK guys, I'm totally confused, which isn't unusual.

Yes It is  Logitech speaker system, that I've had for several years ( I just remembered)

Could you explain to a dummy exactly what driver I have to download, please?

The 790 is very specific

Thank you again.

I went through the procedure, but no joy.

There wasn't a download icon on the desktop like there usually is?

You have to run the exe as administrator

DOTNET 3.5 may need to be installed BEFORE the audio driver

https://www.microsoft.com/en-us/download/details.aspx?id=25150

Sorry, I guess I'm useless at this.

I'm running as Admin OK.

I downloaded (so I thought) the DOTNET 3.5.

and again, there was no means to save on the desktop.

So I really don't know if it's on the PC or not.

How can I tell, please?

Thank you for being patient with me.

Theres nothing special.  Sounds like you may have rootkit malware infected hard drive.

You arent able to to basic things like download a file from a direct link.

A clean install starting from scratch will probably resolve things if you do so from a DVD.

Flash drives are notorious for letting malware hide there so when you reinstall from them they infect you over again.

Region may need to be set on DVD drive before F12 booting works.