Hi branthall89,
Welcome to the HP Community! I see that you are having some sound problems. From what you described with the sound just cutting out and the headphones still working it might be a hardware issue with the speakers. You can check to make sure that your speakers are set to the default sound device. The link shows you how to do it with Windows 7 the only difference for Windows 8 is getting to the Control Panel and you can just search for Control Panel on the main tiles page.
Thank you,