Particle System repeatedly bursting

I have a particle system with two different emitters that both burst once on creation. I create one of these in a BeginOverlap event between two actors. About half the time instead of just bursting immediately and going away the system creates a few particles from each emitter several times, making it look like a smaller explosion is happening repeatedly instead of a single large explosion.

If I hard code the position I create the system then this issue no longer happens. It also doesn’t happen when I use different particle systems. Anyone have any ideas what the problem might be?