Have you restarted your computer?

I did uninstall the sound driver, rebooted, and reinstalled from the mfg website for drivers. According to Device Manager, Realtek properties, I have version 6.0.1.7968 from 10/25/2016.

Yesterday I had the sound go off, and I uninstalled the driver, rebooted, reinstalled the driver, and it worked ... for a while and then stopped again.

(BTW, I edited my original question while you were writing responses.)

What kind of computer is this? Have you looked at your oem's support for a driver rather than Realtek's site?

This is a Dell computer

Processor: Intel(R) Core(TM) i7-7700 CPU @ 3.60GHz

Installed RAM: 16 GB

System type: 64-bit operating system, x64 based processor.

Windows 10 Home, version 1803, installed 5/12/2018

OS build 17134.48

I don't remember exactly when I bought it, but I think it was August 2017, and so I might be able to take it back to the store for repair, as I bought extended warranty.

I have checked Dell's support, and that did not fix the problem. I did find a newer driver at Realtek and installed version 6.0.1.8186, dated 6/14/2017, which had a better installer, but it still does not work.

A few days ago it was not working, but when I put in a DVD to watch, it suddenly started working again, but that trick did not work twice.

Right click on the speaker icon (lower right on taskbar) > Sounds > Playback - and make sure the default is correct and test for sound.

The default is correct, but nothing comes out when I do any of the tests for sound. The speakers stop working right after I watched a video that had sound. The next video I tried to watch did not have sound.

Do you have more than one speaker or sound device in your pc? It's not connecting to the other is it? mine will sometimes default to my monitors even though they don't have built in speakers.

Are the speakers connected via a usb or headphone type cable? are they wireless? bluetooth?

Does it help if you disable and re-enable the speakers?

Last but not least, Dell normally has a pretty decent helpdesk. Have you called them and have them fix it over a chat or call?

I do not have more than one speaker or sound device in my pc that I know of. Realtek is the default. The speakers are plugged into the back of the computer with audio jacks. They are not wireless or bluetooth.

It helped once when I disabled and the re-enabled the speakers, but that no longer helps.

Next I'm going to call the Goodguys at Best Buy (where I bought the computer), as I have a warranty good until Aug 2019. I'm hoping they can help me over the phone - otherwise I might have to take it in.

ETA: I called GeekSquad and they were unable to help me on the phone using remote control of my computer, but the woman I was talking with (who thought it was evening, even though it was 2:30 PM here in California) started an on-line session on Chrome (I'm using Firefox right now), and she said I would probably have to wait an hour for a response. She also said to leave my computer on with the tech support window open. I'll wait and see if they can do anything.

On-line Geek Squad was unable to help me, and they told me to take the computer in to the nearest Best Buy store. I made an appointment to take it back to the store where I bought it in Culver City tomorrow.

I took my computer in yesterday, and GS told me that it was working okay and they asked me to bring my speakers in. So I went back with the speakers and left those, and they called me back saying that the speakers were bad, and so I went back to pick up the computer and bought some new speakers for it, which cost about $129.00. This morning when I hooked up the new speakers, I still had no sound. I do not even get sound from the headphone jack in the front, and GS told me that they did get sound from the headphone jack.

There has to be another issue with my computer, and I think I will let my virus program do a full scan, and maybe that will help. I did a partial scan and it found no problems.

I highly doubt a virus has anything to do with it. Back in the day when an onboard device died the solution was to install a card. Soundblaster and others still make sound cards...

I did a full virus scan, and so I know it's not that now. I was finally able to get sound back by changing the "sound system" in the Control Panel. I just hope it does not go out again!

The only good thing about all of this is that I now have better speakers than I used to have.

I'm glad you got it working. Your experience, however, reminded me of the sometimes questionable value in using services like the Geek Squad to get help. Maybe people don't talk as much about good experiences, but yours is not the first bad experience I've heard about. If I were you, I'd talk to the manager: I think you have a good case for a refund.

On the rare occasion when I have a computer issue that I can't figure out online or on a forum, I typically seek the advice of an independent local shop with good ratings.

I have a warranty with GS, and so what they did was free. I've only had my computer since August 2017, but it crashed just a few months after I had it, and I had to take it in for them to do a restore on it. I tried to do the restore myself, but that did not work.

The new speakers did not have clear installation instructions (no text), and even the Logitech web site did not have information about how to install the speaker or set them up. I found a couple of YouTube videos that were more helpful, but since my speakers did not work, I could not hear them, and so I had to use my tablet to listen to the YouTube videos, which were only partially helpful. Nothing I found told me to change the sound system in the Control Panel.

Installation of speakers usually involves nothing more than plugging in to the speaker or headphone socket

In my case, it did not. Even the headphone socket would not work until I changed the sound system in the control panel. Also, there were no clear instructions of how to plug the speakers in. At first I thought I was supposed to plug a wire from the base speaker to the computer, but later I found that the right front speaker had to be plugged into the computer instead. I only only using the green plug now, but I used to use all the speaker jacks on the back of my computer with my previous speakers.