Emitter always bobbing on X axis in Niagara

In Niagara emitters created from given templates, it is always like the position of the emitter is constantly bobbing back and forth on X axis, of something like 20 units. I notice this e.g. spawning particles at some rate and giving them location inside a cone: the cone is clearly bobbing around the expected emitter origin. How can I control (and deactivate) this movement?