I have Annoying problem ,, I can hear the sound from both headphones and laptop speakers ...?

I recently bought (Dell inspiron 3537), windows 7 64 bit (6.1 build 7601) ,,, more about in first image ,,,

http://i.imgur.com/SBEezVe.png


but I have a problem when i Link headphones to the laptop ... the headphones work good , BUT , I can hear the sound from both headphones and laptop speakers that's problem , i want to hear the sound from the headphones only ,, see the images blow >>>


http://i.imgur.com/lpkKxMp.png
http://i.imgur.com/MXmP6FL.png
http://i.imgur.com/WCpTZCI.png
http://i.imgur.com/ikDKvr1.png
http://i.imgur.com/UIYDAVD.png
http://i.imgur.com/nsrreYQ.png

can you help me please ,, ??