I have attached what I show in my Device Manager for Sound devices. The driver from the Asus website should be good, but you never know. Showing an HD device is fairly normal as far as I know.
But I did have something happen yesterday that was a little strange. My sound was being distorted like I was going through a reverb. I noticed in my mixer settings there was a listing for HD audio volume level. I turned it down and the distortion stopped. The attachment does not show it today, but it was listed like the others.
If not that, check the Realtek settings to see if you have any special effects settings turned up. Also you might adjust which volume source is highest. A good mix between the speaker output on the speaker and the...