I recently bought a Polk Signa S4 sound bar (3.1.2)

When I adjust the volume, it produces static.  This happens whether I use the remote that came with the sound bar, or control volume via the Samsung remote for the TV.  No other buttons on either remote causes this static. There is also static briefly, at startup.

Can anyone suggest something I could easily do to address this?

Or tell me if it signifies a potential defect that could cause me problems later on?

I didn't use the HDMI cable that came with the sound bar.  I already had one plugged into the TV so I used that.  Maybe that is significant.