Semi-transparent surfaces have "hatched" appearance

I am a new user, so excuse me if this is a basic question.

I have created a part (attached) with several semi-transparent surfaces.  Transparency of each surface is set to 0.60 in the illumination settings for the appearance that I've applied.

When I view the surfaces, I see a fine hatched pattern.  It's most visible over a dark background (screenshot attached).  This cross hatch pattern, though faint, is sometimes distracting - is there a way to turn it off or otherwise control it?

I'm using SW2020 SP0.1.

SolidworksGeneral