Duck egg with a sac attached?
This sometimes happens when ducks aren't getting enough calcium or are having other issues with their reproductive systems. Are you able to post a pic of one of these odd eggs? What are you feeding this duck and is she getting extra calcium to help her egg production? That might be the problem.
I was reading someplace, don't remember where as I have been all over the Internet, that the males shouldn't have more than 14% protein. How do I do that as there is only the two of them I can't feed them separately. They are a pair and don't go anywhere in the yard without the other. It didn't say why. Is this something I should be concerned with?
I believe it's just extra calcium that is not so good for the drakes, I haven't heard that extra protein isn't good. But that is why alot of people (myself included) feed a "maintenance" diet year-round and just offer oyster shell on the side for the females during laying season. The girls will eat what they need of that. So yeah, just offer some oyster shell on the side and her laying issues should subside. If they don't though, it might be time for a trip to the vet to be safe as there could be another issue going on.