Network traffic is not stable


I am developing a multiplayer RTS game in UE4 (Armed Island VR - Gameplay (Pre-Alpha) - YouTube), and having some strange issues with networking. I am experiencing 1-2 sec breaks in my network traffic while testing in both LAN / STEAM modes.

Please take a look at the screenshot below taken from the network profiler.

I am using the standard UE4 character class with replication at 30 updates / sec. I am testing with 50 characters battling each other. Projectiles are also replicated, but the issue also exists without any spawned projectiles.

While the traffic is down, nothing is happening on the client side, then the engine is trying to catch up and snaps all the characters to their right places. (Spikes on the graph).

Any suggestions / recommendations are welcomed!

Thanks in advance,
Adam Horvath