i have vgnnr-110e laptop originally came with vista then i upgrade to windows 7 and every thing was working fine.suddenly one day my built in speakers and booting sounds no heared but i could hear whrn i plug my head set into audio output .how ca i get back sound back on my built ins.i tried every thing updating driver from sony,from real tek.i tried microsoft drivers available also. i see the oscillation in the system speaker but no sound.the icon looks blue whereas the icon on internet is clear.can some one help me please