Muscovy Pip

[MrsWard]

Hey folks!
My class has been incubating duck eggs. I saw a small bump-like pip 2 days ago,(day 35) I see lots of shaking and I hear little peeps from the egg, but no real external changes in 2 days. How many days does it typically take after the first sign of pip?

Thanks for helping a newby out

 

[Pyxis]

2 days is quite a long time with no progress. What's the temperature and humidity in the incubator? Is it forced air or still air?