Erratic motion in any physics sim is usually caused by a substeps issue. Try turning that up, that should help. It’s because when RayFire is simming a particle(geo, w/e) from point A - B, if it’s moving too fast it needs more information about where that Particle is.
If that’s confusing, imagine you wanted to have an animation of a ball bouncing from one side of the room to another in 100 frames. Well if you had 1 keyframe on frame 1 and another on frame 100, that’s not enough information. If you add another keyframe on frame 50, you know where the ball is in the middle of the animation. If you keep adding more information, you will get more detail in the animation. It works the same way with physics sims. If it’s traveling too fast, it needs more information to know where it’s been, going, current location.