When I label my contours at 1"=40 and text size 0.1 my contour labels look fine.

When I change the scale to 1"=20' for a detailed view of an area, the contour label text is smaller (0.5) as it should be. However, I get these lines above and below the contour label that appear to be hidden behind the text mask at 1"=40' and show above and below the label at 1"=20'

Any suggestions how to make these lines go away. They are stopping publication of our project.