Are both of those feeds a whole grain type feed or a crumble or pelleted feed?Mixture of Scratch and Peck and Purina Organic plus grit and oyster shells.
If whole grain this could be an issue because it gives the birds the option to pick and choose which seeds/peices they want to eat or not eat and that causes an unbalanced diet which in turn causes stuff like you are seeing.
Not getting a balanced diet can lead to overweightness which them makes the birds much more susceptible to these issues.
Do you feed scraps, scratch, mealworms or any treats too?