Pro9000 - Smudge on top middle of prints... What do I clean?

[muzicman82]

I have a Canon Pro9000. Sometimes, I get a dark smudge on the top center of the print side of prints. The rest of the sheet is OK. The paper is flat with no problems. It is Red River 45lb SemiGloss.

Below is a scan of it. I also have a 600dpi scan if interested, but I think you can see what is happening here. Not sure what to clean.

Also, this is from a borderless print, but I'm not sure that matters.

Thanks!