Interactive pdf with some objects in dull colors

Hi,
I'm in the final stages of a semester assignment and hope someone can help me...

I have an InDesign document with only RGB colors. When I export it to an interactive PDF, I notice that the same RGB color appears faded on some of the pages within the same PDF, as if it's in CMYK in some places, even though I've double-checked that the exact same RGB swatch has been used. And there are no elements with multiply or any othe layer styles.

I need everything in RGB, hoping someone can help me! 🙂

These two screenshots are from the same interactive pdf document: