My collegues has the same Indesign version installation.
Since yesterday, they export PDF ready for print and all was ok.
Yesterday the same PDF had a problem: in the PC of the first collegue, PDF was ok and had 80% of b/w; in the PC of the second with cmyk and the color is not the same.
They want to have the same PDF with the same percentual of colours.
We've seen all Preferences (in Indesign and Distiller) and everything is the same.
What can they do?
Try using the PDF/x-4 preset. If an all CMYK PDF is required, set the Color Conversion to Convert to Destination, and the Destination to Document CMYK.