Prior SU4 you had no issue ?
Not sure if it is the exact same issue but have a look at this post: MCDU and Avionics Freeze When Importing SimBrief FP in Inibuilds - #3 by dpll18
Prior SU4 you had no issue ?
Not sure if it is the exact same issue but have a look at this post: MCDU and Avionics Freeze When Importing SimBrief FP in Inibuilds - #3 by dpll18