Here’s a problem I’ve been getting a lot recently … and a solution!
Elements not printing out or printing out darker or fainter than they should. Why? The element – beit type or a box or anything – has been set to overprint.
Overprinting is great. Black type on a tinted or coloured background is much better overprinted. Problem is, further down the production process, maybe the black type gets changed to white and promptly disappears!
Two things you can do (assuming you’re printing from PDFs).
One. Check the file with Overprint Preview ticked in Acrobat 6 and above.
Two. Instead of locating the offending element and switch the overprinting off, simply go in to advanced settings in Distiller and uncheck the Preserve Overprint box.
I’ve only just found out about it!