OK.
There are no W7 audio drivers for that audio chip.
The only suggestion I can offer is to download and run the XP driver from the link below.
Close out of any error windows.
Go to the device manager and click on the multimedia audio controller needing drivers.
Click on the driver tab. Click on Update driver. Select the Browse my computer for driver software and browse to the driver folder that was created when you ran the file. That folder will be located in C:\SWSetup\sp28482. Make sure the Include subfolders box is checked and see if the driver installs that way.