Rpm not displaying on screen when starting

[Plane_Maintenance]

My system is not indication after start up the avionics master have to be cycled once or twice before the system display RPM.

any help

 

[Dynon]

A few questions that will help us:

Which of our products is this?
What kind of engine is on it?
What kind of ignition system is on the engine?
What is your normal startup sequence?