Streaming Levels not reloading on clients

I’m running UE 4.11.2, and am having a peculiar issue with round restarts for my map.

I’m running a dedicated server with remote clients.

I have “overlay” objects, like object spawn points or triggers, stored as streaming levels that I load with the map, and unload/reload at each round end, just before the start of the next round.

The issue, is that the “add-on” level randomly doesn’t load on all clients. Clients with lower GPU power have the issue more often than clients with higher end hardware. Mind you, the objects within these “add-on” streaming levels are very small and very few. Typically only being a few Actors of various types, not huge extensions of the map.

This is what I see in the Client Log file when the problem occurs:
LogNet:Warning: UActorChannel::ProcessBunch: SerializeNewActor failed to find/spawn actor [actor content path, Channel #]

The path that the error displays is valid, and like I said, it doesn’t happen consistently; so it can’t be an actual path related problem. I haven’t been able to find much useful information in regards to this error.

The initial start of the map works just fine. The problem will only occur when I reset the map prior to the start of the next round by unloading the stream level, and then loading it again. I do it this way so that the objects that are spawned within the stream level can execute their initialization (at spawn) code & their “BeginPlay” function.

I tried enabling the “Should Block on Load” option, but that had no impact.

Should I add a delay between unloading and reloading the stream level?
Or does anyone have any other suggestions?

One final tid-bit that might help… I’m doing this through the GameMode Blueprint, and am not currently using Level BluePrints.

Adding a small delay after unloading the level, before the level is reloaded took care of the issue.