Are you saying the problem only occurs when printing as pdf? If so, I would suspect the pdf software you are interfacing with.
It appears as though you are using many different fonts in the upper view and that it is trying to be translated into just 1 font style with different sizes.
We rarely just send this to the printer however regardless of choosing print to pdf or just print the preview shows this distorted text. The text is all the same font with two different sizes in the top group of text. Notice the dimensions are also affected. One moment print preview looks the way it should but if I close the preview and make an adjustment it will distort the text when previewed again. This is inconsistent but happens more often than not. This happened with 2012 and suddenly stopped. Now this is 2013 and all of us are having this issue. We are using DELL workstations with Windows 7 and Quadro video cards.
We did just discover that a rebuild when this happens will render a perfect preview. But it goes right back to being distorted if you make a small adjustment. Then another rebuild sets it straight.