Windows 7 - Sound Won't Work "Error failed to play test tone"

Hi. I have had some problems recently with my PC, and the latest is that my sound doesn't work. I have Realtek HD Audio.

I can still see my speakers under the Sound list in Control Panel, and they say they work. All of my drivers are up to date and say they work.

I have tried many things, some of which where disabling all sound effects under enhancements, reinstalling all the drivers, and restarting the Windows Audio.

Also when under Speaker Properties and in the advanced tab when i press test i get an error message that says failed to play test tone.
Please Help! i have spent many days trying to find out how to fix this, and i need sound. Thanks

The first thing you need to do is make sure that you have a Realtek card.

Download a program such as Speccy: Speccy - Download

Once you've confirmed your sound card, download the latest drivers straight from the Realtek website.

In the case of HD Audio drivers:
Realtek

Now uninstall your old drivers using the Device Manager.

Once your old drivers are uninstalled, you'll need to install the new ones.

If your sound card still isn't working after confirming the make and model and installing the correct drivers you likely have a problem with the card itself. If you have an independent sound card you could try using the onboard sound instead, however Realtek is usually the onboard sound so I'm guessing that's your only option.

If you were planning on upgrading your sound from Realtek anyway, you could buy an independent card from a company like Creative or HT OMEGA. You can find good cards such as the X-FI and the OMEGA Striker for about $60 at Newegg.com

If you don't want to replace the card, you should probably exchange your motherboard for a new one after you've exhausted all of the software options and tested your speakers on a secondary source to make certain they're working properly.

Thanks for your help. I made sure it was a realtek card and did all that you said, but my sound still doesn't work. Yeah, my soundcard is part of my motherboard. Also, i really dont want to spend much money on a new sound card. Is there no other things that cud be wrong? I have seen a couple fixes for Windows Vista that had the same problem, and they just had to delete a file in the registry to make their sound work again.