NPC (gameObject) inactive when out of field of view/player not active

Hey together,

I am working on a multiplayer game with NPCs also included. One Server is synchronizing the NPC activity, let's say it is responsible for their activities, sending their state to the other machines. On this server also a human player can act though. As it is a multiuser game and I'm sometimes testing alone, I experienced that when I leave the server alone to play on other machines in the same game, the activities of the NPCs are stopped, when there is no human player action on the server. It seems that if the NPC-objects are not in the field of view or the player is not doing anything, the server game will not continue acting. I have no idea where to search for this problem, but I had the idea that this could be a mechanism for saving rendering/computing power in Unity?! If I play again on the server machine respectively the NPCs are in the field of view again, they sometimes continue acting and on all machines everything works fine.

Has anyone a suggestion what the reason might be and if, how to solve this? I can be more detailed if needed, but I think the problem is clear?! It seems to me that Unity is neglecting objects that are not in focus. Thanks in advance and best regards,

RunRun