diff --git a/Classes/CoreManager.swift b/Classes/CoreManager.swift
index 624a46fa3..7eb83bc83 100644
--- a/Classes/CoreManager.swift
+++ b/Classes/CoreManager.swift
@@ -41,6 +41,10 @@ import linphonesw
 	}
 
 	@objc func startIterateTimer() {
+		if (mIterateTimer?.isValid ?? false) {
+			Log.directLog(BCTBX_LOG_DEBUG, text: "Iterate timer is already started, skipping ...")
+			return
+		}
 		mIterateTimer = Timer.scheduledTimer(timeInterval: 0.02, target: self, selector: #selector(self.iterate), userInfo: nil, repeats: true)
 		Log.directLog(BCTBX_LOG_DEBUG, text: "start iterate timer")
 
@@ -48,8 +52,8 @@ import linphonesw
 
 	@objc func stopIterateTimer() {
 		if let timer = mIterateTimer {
-			timer.invalidate()
 			Log.directLog(BCTBX_LOG_DEBUG, text: "stop iterate timer")
+			timer.invalidate()
 		}
 	}
 }