SSD ? Set Sound Device allows you to output sound to more than one audio device as Windows XP used to.SSD enables you to change the default Sound Device via the commandline. To call SSD from the commandline, the syntax is ?SSD.exe #? (where # is the number of the Sound Device to select from the list,?Select Default? dropdown box must be enabled to make device selectable).While originally written for Windows 7, users have reported success from Windows 7 all the way up to Windows 8.1.