I found an old discussion about pretty much the same issue but there wasn't any answer.
My videos colors change when I upload them on Youtube. Colors look roughly desaturated. I can fix this by rendering really saturated video but is there any other way to avoid colors to change?
I'm using premiere pro cs6 and Windows. I used h.264 settings but I think I had this same problem with other settings too (but not sure). Should I try with other render settings or are my Premiere settings wrong?
Problem solved! Somehow the problem was my internet browser, Google Chrome. With other browsers I didn't have the color problem. And after reinstalling chrome it also works fine with Chrome.
Having the same problem and googling lead me here. Really weird.
I guess I'll have to try it too.