diff --git a/MachMgrPhases.cpp b/MachMgrPhases.cpp
index 64d18d6..2acb8e0 100644
--- a/MachMgrPhases.cpp
+++ b/MachMgrPhases.cpp
@@ -236,7 +236,8 @@ MachMgr::RemoveLastPhase( void)
   // se era corrente, rendo corrente la precedente
    if ( m_nCurrPhase == m_nPhasesCount)
       SetCurrPhase( m_nCurrPhase - 1) ;
-   -- m_nPhasesCount ;
+  // ricalcolo il numero delle fasi (per maggior robustezza)
+   m_nPhasesCount = CalcPhaseCount() ;
    return true ;
 }