When setting a new field value, it is filled (populated) four times – why?

we have a major business object “CI - computer” (group member).  It has a field “Primärer Benutzer” (“primary user”) that holds a customer name.  If we set the field value using an object picker, the value is set four times by Cherwell:

Observations we made so far:

  • There are no auto-fill / auto-populate rules on the primary user field, nor can we identify any relationships that would auto-fill that field.
  • The value is set four times when using an object picker and only twice when doing it “manually” in a onestep.

My questions are:

  1. Why is Cherwell setting the value more than once at all?
  2. What could possibly be triggering that?  (As I said, we can’t find any auto-fill rules for that field.)

I'd be grateful for any hints as to how this auto-fill is triggered or how I can inspect the issue in more depth.