Hi CrunchyThunder and welcome to Windows 7 Forums
Unfortunately, I cannot ascertain whether you have Realtek audio or some other audio device (other than the HDMI output, which, as you say, is working). A quick search on the model number,
vcpsa 390x, reveals it to be a Sony laptop, however no audio information is available.
With reference to
Hardware Identification, can you supply the information shown in
RED and BLUE for each item shown in the Sound, video and game controllers category.