diff --git a/src/mainwindow.cpp b/src/mainwindow.cpp
--- a/src/mainwindow.cpp
+++ b/src/mainwindow.cpp
@@ -117,7 +117,7 @@ MainWindow::MainWindow(QWidget *parent) 
             this, &MainWindow::onNumOfSamplesChanged);
 
     connect(&plotControlPanel, &PlotControlPanel::numOfSamplesChanged,
-            ui->plot, &Plot::onNumOfSamplesChanged);
+            plotMan, &PlotManager::onNumOfSamplesChanged);
 
     connect(&plotControlPanel, &PlotControlPanel::scaleChanged,
             plotMan, &PlotManager::setAxis);
diff --git a/src/plotmanager.cpp b/src/plotmanager.cpp
--- a/src/plotmanager.cpp
+++ b/src/plotmanager.cpp
@@ -364,3 +364,11 @@ void PlotManager::flashSnapshotOverlay()
         plot->flashSnapshotOverlay(darkBackgroundAction.isChecked());
     }
 }
+
+void PlotManager::onNumOfSamplesChanged(unsigned value)
+{
+    for (auto plot : plotWidgets)
+    {
+        plot->onNumOfSamplesChanged(value);
+    }
+}
diff --git a/src/plotmanager.h b/src/plotmanager.h
--- a/src/plotmanager.h
+++ b/src/plotmanager.h
@@ -62,6 +62,8 @@ public slots:
     void setAxis(bool autoScaled, double yMin = 0, double yMax = 1);
     /// Display an animation for snapshot
     void flashSnapshotOverlay();
+    /// Should be called to update zoom base
+    void onNumOfSamplesChanged(unsigned value);
 
 private:
     bool isMulti;