You probably have different versions of the fonts and they are not embedded in the PDF. Did you make the PDFs that you are placing?
Yes sir, I made the pdfs myself on the same computer that I'm using.for indesign.
- How did you make this PDF? Did you embed all used fonts, at least subsets?
- In which application the PDF have been created?
- Do the fonts permit to embed them?
- Have been installed all styles of your font?
Have you updated the OS since the PDFs were created?