In InDesign 3.01, I have this strange picture frame that is added when I make a PDF via export. It doesn't appear when I Distill a PS file for my printer, it is not on any master page, or nay hidden layer. It was never on the page in question, at least, not in that position. The frame's fill (Red, to spot poor cropping) is used throughout the document for other picture frames.

What gremlin inserted this into my page? How do I make PDFs without this goddam box?