I have a ASUS G1Sn I stupidly installed a driver updater and it installed new updates for my audio drivers. I had my headphones plugged in at the time and when it finished the updates my headphones worked fine. I then unplugged my headphones and discovered that the speakers weren't working but were working fine before I installed the updates. So I decided update the drivers again with my headphones unplugged the speakers worked, thought I had solved it until I plugged in my headphones and found that they weren't working. I've tried reinstalling the drivers now only the headphones work, I tried updating them and then downloading the 'originals' from ASUS but nothing has worked so far.

Try to restore Your windows to a point in time where You didn't have updated the drivers yet.
If You don't know how to do that, but have no problems reinstalling the windows- re install it then. That often helps :)