Did a last state restore during climbout after having to leave and close X-Plane unexpectedly, and upon restore A/P disco (fine, kind of expect that), but the pressurization system was completely unstable until I cycled the packs off, let the rates calm down a bit, then back on. Kept cycling, rapidly, from a 2000+ cabin climb to a 2000- cabin descent. Might be a state restore problem, unfortunately, it was a "last state" restore so got overwritten almost immediately. I'll try to reproduce later and make better notes of what is happening, and after I complete this flight I'll attach the FDR csv.gz's from the Output/CL650 folder.