Want to change your Default Sound/Audio device without removing your 3.5MM JACK from your laptop by a simple shortcut ???

Step1: First download & install Autohotkey (just 2Mb simple program) from the below link. 

(Autohotkey is a very famous simple tool to automate ur work in windows.)

http://www.autohotkey.com/download/

Step2: Save the below script as a Change_Audio.ahk file then open the Change_Audio.ahk. 

When you press (Windows + Shift + A) keys in your computer, your computer's default audio is changed.

;*********************************************************************************
; Change your Default Sound/Audio device without removing your 3.5MM JACK from your laptop.

; Shortcut to switch the Defalut audio device.  Windows Key + Shift + A
#+a::
Run, mmsys.cpl
WinWait,Sound
ControlSend,SysListView321,{Down}
ControlGet, isEnabled, Enabled,,&Set Default
if(!isEnabled)
{
 ControlSend,SysListView321,{Down 2}
}
ControlClick,&Set Default
ControlClick,OK
WinWaitClose
SoundPlay, *-1
Return
;***************************************************************

Know more about AutoHotKey from the below link.
http://www.autohotkey.com/docs/Tutorial.htm