Multinstance bpm produces Implicit flush due to query execution

Hi, we being using BPM Activiti for a long while, but now in production we having some wrong assignments in the ProcTask creation, we suppose due to the volume of simultaneous users. The problem become when executing a multi-instance task that causes “Implicit flush due to query execution” and apparently some procActors are wrong assigned to ProcTask (in the attached image same Actor is assigned repeatedly). We want to known the impact of “Implicit flush” can have on data, and if this debug warning can be the cause of wrong assignments.
As i said before in test enviroments this works correctly.

Could it be that for this particular process instance you had multiple process actors for the same process role with the same user?