LCD Speaker Bar Sound: Mushy with Static

I use the LCD Speaker Bar (Model NQ576AA) with the Z Display monitor. Problem #1: The sound is mushy, as if underwater. Problem #2: There is a static-y noise that it emits when, for instance, I play a YouTube video, but also when I use the (wireless) mouse scroll button -- I scroll down the page and get a static-y noise, like walking on dry leaves, with every scroll -- and there is no sound involved.

For #1: I've tried different settings in the Sound Properties Enhancements tab -- any suggestions for the clearest sound for a speaking voice?

For #2: Interference from something?