Int 1A Fn FF04  - Snd - Play Music String In Background                    [s]

   AX = FF04h
   DS:DX -> ASCIZ music string

Return: AH = status
       00h successful (music begins playing in background)
       01h busy

Note:  the music string accepted by SND is not the same as that accepted by
     BASIC and other programs which process music strings

See Also: AX=FF00h,AX=FF05h,INT 80/BX=0006h