Sudden FPS Drop When Loading Sublevel

Hi all,

As I have a relatively large map, I am using level streaming to stream in and out small chunks of my open world map. The actual level streaming works fine, but every time a sublevel streams in or out, the FPS goes from 70 to about 3 for maybe a tenth of a second, and this makes a really noticeable jerk. This means when the player moves around the map, every now and then this jerk happens. I imagine this is related to the sublevel trying to stream really quickly all at once - but I would rather it streams slower and doesn’t have such an impact on the FPS. How can I force it to do this?

Thanks!