[HiassofT]

I mean, if i rapidly press any buttons several times on my harmony remotes (i have one hub in my living room and one hub in my sleeping room), my NUC reacts without any delays, more straighter, compared to my HTPC with my RC6 IR-Receiver.
Both Hub's/Harmony's are having the same setup.

Interesting. I currently have no real explanation where this could come from.

Can you check if remotedelay is set identically on both boxes? https://kodi.wiki/view/advancedsettings.xml#remotedelay Just a wild guess, not 100% sure if that could be responsible but it'd still be worth to check.

Another idea: could you plug the USB IR receiver into your NUC? Just cover the built-in IR receiver of the NUC with black tape or put a book in front of it so only the USB IR receiver gets the signals.

With new build #0418 everything works - many thanks!

Thanks a lot for reporting back!

so long,

Hias