Go to the edit menu and select Preflight. Once the window opens look for 3 small icons at the top, click on the last one to the right (the wrench). Expand the category called "Color spaces, spot colors, inks", select "Correct 4c Black", click on the fix button on the bottom right.
It doesn't work will all documents but give it a try. If it doesn't you can try duplicating the fix and modifying it in case the black values fall out of range. Hope this helps.
I tried this but unfortunately it didn't change the values of the rich black. I tried modifying it but that didn't work either.