I don't know if this helps. But I was having the exact same problem with a specific logo I was working on. I think the source of the problem came originally from a piece of work that was made in Corel. Elements of that corel file lingered or leftover in some fashion in the other files associated with that particular company's files. I found when I opened a new document, my colors would be fine. For that particular document I went into each swatch and corrected the color.
To make sure it wouldn't happen again I opened a new document, checked to make sure the swatches were correct and saved the default swatch library to call up when I need it. I also have a personal swatch library that I keep on persistent with all the standard default colors saved.
I don't know if this helps. But I was having the exact same problem with a specific logo I was working on. I think the source of the problem came originally from a piece of work that was made in Corel. Elements of that corel file lingered or leftover in some fashion in the other files associated with that particular company's files. I found when I opened a new document, my colors would be fine. For that particular document I went into each swatch and corrected the color.
To make sure it wouldn't happen again I opened a new document, checked to make sure the swatches were correct and saved the default swatch library to call up when I need it. I also have a personal swatch library that I keep on persistent with all the standard default colors saved.