(XBox) DA 40 throttle/engine speed issues

This is another odd one.
I can’t replicate it, (just tried again)
But it seems you aren’t the only one.
Here are a couple links to existing threads I have found.
1)

https://forums.flightsimulator.com/t/default-diamond-da40-engine-performance-excessive-rpm/390729?u=thesevenflyer

I hope the issue gets resolved.
Good luck.