I am having the same problem you are. My Sound/Playback tab looks the same with the only two options being the Speaker (Realtek) and Realtek Digital Output. However when I click under "jack information" I only get one option, which is listed as "ATAPI internal ATAPI jack". Last night I was able to get it so that sound was coming through both the headphones and speakers. I was able to mute the speakers manually, and that worked, but I accidentally reverted the settings.
I've also re-installed the drivers
, but nothing seems to help the problem. I'm running this on a laptop, model ASUS U41S. Any help would be appreciated.