I've noticed that sometimes my king/prince/sultan's influence is reset to 0 and then grows by one pr. year until it reaches it's former level. Has anybody else noticed this and is there an explanation for it.

Premises: This has happened in situations without any wars (even neutral with the rebs), The king stationary in the heart of the empire (coastal with full access).

It can be a bit annoying since troops produced at very low influence have very low loyalty. Also any heirs coming of age will be pretty crappy.

Has anybody else seen this?