Hi i am currently running a XPS 720 with Windows 7. I have had Windows 7 on the machine for years and only recently have experienced sound problems. Audio Does not play, or play a test tone. Audio also doesnt work with my USB Gigaware Headset(basicaly its own external soundcard).
I have tried the following steps.
-Downloaded and Installed the newest Audio driver 'SIGMATEL STAC 92XX C-Major HD Audio Driver Version A03'. -Purchased a new external sound card thinking that may be the problem. I disable the onboard soundcard prior to installing the new drivers. After installing it, i troubleshooted it in every which way, to get it to work and play a test tone or sound. Many long calls with Diamond customer service (the new cards manufacturer) but no luck. -Removed PCI soundcard and re enabled onboard audio. -Removed the video driver and reinstalling the current one without the audio. -tried restarting the windows audio service in services.msc -Uninstalled a Windows Update that was said to cause the sound problem (link below)