A lot of people are looking for the Sigmatel audio driver for Windows 7. The short answer to this quesstion is that there is NO Sigmatel audio driver for Windows 7. The company’s PC audio solution was bought by IDT, and the support for it has been discontinued.
Fortunately, there is a way to work around the problem. There are Vista drivers available for Sigmatel audio, which you can try to install on Windows 7. Here are links to the Vista drivers:
If you have a Sigmatel 975X sound card, there is no Vista driver for it, and I doubt that the XP driver would work on Windows 7.
Let us know if this works for you, and please tell us the make and model of your computer. Thanks.