Yes, CB, understand you, i mentioned befor, i note some "random" behavior too.
Try adjusting Max and Min Height near the surface.
Try narrowing the active sonar beam, it is 180 deg wide by default, 120 (60L-60R) with Jungmans settings, 180 is a crazy thing, if 180 is the limit for the sweep arc, OK, but it works as the wide of the beam, and it is not real, is a superwide ping.
Narrowing the active sonar will limit both, beam wide and sweep arc, may be not real, but it is a program limitation, we can not set the beam wide.
Making it more narrow we enforce them to locate you with pasive sensor and iluminate you with the active more in front of them.
Try and comment.