I am generating PDF files from Latex and embed graphics with includegraphics command: these can be bitmap images (PNG, JPEG) or vector graphics (PDF generated from e.g. inkscape or mathematical plotting software as gnuplot). I have an issue with some pages in the same document having a lesser print quality than others: the text is pixellated. This happens on pages where vector graphics are included, but not on pages where bitmap images are included.
What is the reason for this? Is there a workaround (other than convert my vector graphics to bitmap before embedding it in PDF!)