Iplot adds hatch-like lines to certain elements

We are creating a sheet file in Microstation to send to our local DOT, but one of the sheets has started printing these weird perpendicular lines to some of the curves in the drawing. It seems to be limited to one particular reference, but identical sheets that use the same reference, though they plot a different location in the reference, don't have the same problem. The lines do not appear in the dgn or any of the references, they only appear in the plotted pdf file. I've tried using the "verifydgn" and "fixrange" key-in Microstation tools, as I saw them suggested on a separate post, but that hasn't done much. Any ideas?