acer aspire 9300 tv-out problem

hi, i have an acer aspire laptop model 9300 and the graphics card is a nvidia geforce go 6100, all of a sudden the s-video output wont work, normally i hook it up then press Fn and F5 and it lets me choose the display either on laptop, tv, or both. Now it only lets me choose the laptop. Other than this the laptop works fine and i have tried the recovery disc which blanked the hardrive and reinstalled windows with all drivers and factory settings and get the same problem.

any ideas?