You have SP3 and HD audio give this a try:
This patch is required before any of the HD device drivers are installed
1. On your PC change the CSDVersion registry key to XP SP2:
2. Restart your PC
3. Install KB888111xpsp2.exeHD_Audio/kb888111xpsp2.exe
and your audio driver.
4. Change the CSDVersion key back to XP SP3 again:
5. Restart your PC, finalize configuration of your PC, sysprep and capture.Simplified Directions
Goto Start>Run and type in regedit , then click OK.
Click the plus signs in front of HKEY_LOCAL_MACHINE, SYSTEM, Current Control Set, Control, and finally, click Windows.
In the right panel you will see CSDVersion.
Right click it, choose Modify.
In the highlighted input window, you should see 300. Change it to 200.
Click OK, close regedit and restart your PC. Windows will now think it is SP2 and allow you to install the UAA and your HD audio driver.
Make sure to reboot and then test your sound BEFORE, changing the value back to 300.
Then follow the same steps to change it back to SP3. Change the 200 back to 300.