Mine started chirping from inside the egg early on day 20. 

Well, I have quite a time getting the temps up. This is on the egg-o-meter. The thermometer at the top of the eggs is OK. I think it will be OK. I don't hear anything or see any movement. Humidity is 67%. I am constantly checking. When should I hear chirping or see rocking? I will keep everyone posted ( posting keeps these fingers busy ).