The first sonic boom prediction workshop which was held in January 2014 has issued three test cases to be compared by a wide range of participants from the international sonic boom community, each one using their own numerical methodology. The present paper is dedicated to the analysis of the results obtained using three different solvers: CEDRE, ENGENIE and WOLF. What is meant here is to assess the sensitivity of the flow pressure perturbation used for acoustic propagation with respect to usual CFD ans mesh practices. Moreover, this work is a contribution toward building up the knowledge allowing being able to say what can be considered as a valid numerically predicted near field pressure.