Transparency Issues When Printing Illustrator File

I'm having a problem when I print a PDF or an AI file, a black box shows up around the transparent figure in the left corner. I've tweaked all of the transparency flattners to no avail. When I export as a JPEG the box isn't there. Its just driving me crazy because I'd like to send the client a PDF not a JPEG. Attached is an image of what the box looks like when printed. Any and all help is greatly appreciated.