Sunday, March 29, 2009

SIGMATEL STAC 92XX C-Major HD Audio and Vista On A Dell E1505

When Windows Vista was first released a certain hardware manufacturer was also going through a change - SigmaTel. In July of 2006 SigmaTel was advised to sell their non-profitable PC audio division and take a loss so that they can concentrate their efforts on their other products. On August 1st of 2006 SigmaTel sold its PC audio division for $80 million to Integrated Device Technology (IDT). What does that mean you ask? Well, the timing sucked. IDT was more worried about the changeover and less worried about the upcoming new OS release so no new driver was made for Vista running SigmaTel audio hardware! Even Windows XP owners had issues with newer boards equipped with SigmaTel audio because there was no option for Stereo Mix included with the latest XP drivers either. So who is affected by this problem? Just about everyone who purchased a Dell, HP, Gateway, Compaq, or Acer PC or laptop with Sigmatel audio. That's a lot of people! That's a lot of complaints! Dell seems to care little about it. They claim that it only affects a small number of people. How about everyone who purchased a Dell computer with a SigmaTel audio chip between December of 2005 and March of 2008?!?! Almost every Dell made during that time used SigmaTel. Dell says that the problem has been fixed in Windows XP - which it was, so why not Vista?

Some claim that it has to do with DRM restrictions imposed by the government (thanks RIAA/MPAA bastards!). Disabling or not even having the ability to use stereo mix keeps the user from recording live audio streams without use of a third-party program that usually one has to pay for. You also can't record through your microphone. That leaves out many musicians who like to record and edit their work using their PC's. Did Microsoft do this on purpose? The Conspiracy Theorists would love it if you believed that. My take is that SigmaTel/IDT was just too busy to care or the new company didn't have the technical savvy to recognize the potential for a problem in time and just missed the boat. Because of this the PC manufacturers were forced to modify or write their own drivers to give the unit at the very least least minimal functionality.

I have had my Dell Inspiron e1505 running Windows Vista Ultimate for over two years now and never even noticed that I had an issue until I tried to use Audacity ( to record some audio from a video that I was watching and it didn't work. A quick Google revealed pages and pages of people with similar problems. Now I'm not going to say that I came up with this fix all by myself. I actually spent many hours trying out multiple "fixes" that people had claimed that worked before coming up with this one on my own. I have since found out that others also discovered this method that I used so I'm not going to even try to take any credit on this one.

Disclaimer: The following procedures to restore SigmaTel stereo mix functionality has only been tested on a Dell Inspiron E1505 laptop with SigmaTel 92XX audio. There is no guarantee that this will work on your particular system - even if it's the exact same as mine. Try these methods at your own risk and good luck!!!

Using this method will cause the SigmaTel Control Panel extension to crash with a COM error. You can search your system for the .CPL file for the SigmaTel function and delete it or just leave it and deal with it. It won't crash your system by leaving it there. It's just annoying if you accidentally click it.

The solution:

This file will install driver version, A11 and should state so in the description of the driver.

2. Right-click the R171789.exe file and select "Properties".

3. Go to the Compatibility tab.

4. Select the box that says "Run this program in compatibility mode for:" and then choose "Windows XP (Service Pack 2)".

5. Also check the "Run this program as an administrator" box.

6. Close the dialogue and install!!!

No reboot is necessary.

Now go to your Control Panel and choose "Sound" and the "Recording" tab and you should now see Microphone, Line In (which is the microphone jack when it's not being used with a mic) and Stereo Mix. It removes the SPDIF setting but the jack still works using the Stereo Mix settings.

Have fun!!!

Edit (07-29-2015) - It appears that Dell has killed off the page with the link to download that driver. I will find an alternate source and post it here when I can.


Greg Sandow said...

I've done this. And I'd love to know if this driver will also work under Windows 7. Has anyone tried it?