Disable lock screen sound ??

[-nVIDIA- (OC)]

Hi everybody, everytime i have my omnia in my pockets and the pen hits the display it allways makes a sound. It really pisses me off -.-
I uploaded an pic, everytime i hit the red box it makes that sound "beep".. help me out guys please im about to freak out !

http://img5.imagebanana.com/view/77xu8bv7/wm65lockscreen2Kopie.jpg

thanks allot

[-nVIDIA- (OC)]

help please help !
i cant stand that sound anymore. i know you guys can do it so please give yourself a little push and help me out please...