Hi and welcome to the site
Did you follow the sndvol32.exe procedure exactly?
To resolve this issue, extract a new copy of Sndvol32.exe from the Windows XP compact disc to the system_root\System32 folder on your computer's hard disk. To do this, follow these steps:
1. Insert the Windows XP CD-ROM into your computer's CD-ROM or DVD-ROM drive. Press and hold down the SHIFT key as you insert the CD-ROM to prevent it from starting automatically.
2. Click Start, and then click Run.
3. In the Open box, type cmd, and then click OK.
4. Type the following lines at the command prompt, pressing ENTER after each line, where CD-ROM drive is the drive letter of the computer's CD-ROM or DVD-ROM drive that contains the Windows XP CD-ROM, and system_root is the path and folder name where the Windows system files are located (generally C:\Windows):
CD-ROM drive:
cd i386
expand sndvol32.ex_ system_root\system32\sndvol32.exe
..or did you just copy the file there?
You might want to try this suggestion from annoyances.org
Right-click on My Computer
>Click on Manage
>Expand 'Services & Applications'
>Highlight 'Services'
>Look through list of services on the right....
>Find Universal Plug & Play Device Host
>Right-click on it.
>Click properties.
>Change startup type to 'Disabled'
>Do exactly the same with 'SSDP discovery service'
>Problem should be solved.