Tim Willson said:Try going to Tools > Color Management and changing the setting to Color Management Off. I have trouble with RGB and CMYK all the time (usually it's RGB that looks better), and changing this setting can help.
Disable color management is a big error. All files will have a color profile anyway (for display and print), just you don't have control about it.
Tim Willson said:One other discovery was that if I have ANY element of CMYK in a file when I exported as a press-ready PDF, the color would fade out and look terrible.
That means: "you're using RGB color mode and publish as PDF as CMYK without using a color profile". If you will output as CMYK PDF, you should use a CMYK color mode and CMYK color profile. If you use the right clor profile, the colors will look as the printed result. Of course, the bright of the RGB colors are not possible to print