diff --git a/pandatool/src/gtk-stats/gtkStatsFlameGraph.cxx b/pandatool/src/gtk-stats/gtkStatsFlameGraph.cxx
index 08291038b8..dcd1491485 100644
--- a/pandatool/src/gtk-stats/gtkStatsFlameGraph.cxx
+++ b/pandatool/src/gtk-stats/gtkStatsFlameGraph.cxx
@@ -199,6 +199,9 @@ normal_guide_bars() {
   }
 
   _guide_bars_changed = true;
+
+  nassertv_always(_scale_area != nullptr);
+  gtk_widget_queue_draw(_scale_area);
 }
 
 /**
diff --git a/pandatool/src/gtk-stats/gtkStatsGraph.cxx b/pandatool/src/gtk-stats/gtkStatsGraph.cxx
index f16fdd2287..5798a07833 100644
--- a/pandatool/src/gtk-stats/gtkStatsGraph.cxx
+++ b/pandatool/src/gtk-stats/gtkStatsGraph.cxx
@@ -33,11 +33,6 @@ GtkStatsGraph::
 GtkStatsGraph(GtkStatsMonitor *monitor, bool has_label_stack) :
   _monitor(monitor)
 {
-  _parent_window = nullptr;
-  _window = nullptr;
-  _graph_window = nullptr;
-  _scale_area = nullptr;
-
   GtkWidget *parent_window = monitor->get_window();
 
   GdkWindow *window = gtk_widget_get_window(parent_window);
diff --git a/pandatool/src/gtk-stats/gtkStatsGraph.h b/pandatool/src/gtk-stats/gtkStatsGraph.h
index ca0a6b9954..bd2f333987 100644
--- a/pandatool/src/gtk-stats/gtkStatsGraph.h
+++ b/pandatool/src/gtk-stats/gtkStatsGraph.h
@@ -96,14 +96,14 @@ protected:
   TextColors _text_colors;
 
   GtkStatsMonitor *_monitor;
-  GtkWidget *_parent_window;
-  GtkWidget *_window;
+  GtkWidget *_parent_window = nullptr;
+  GtkWidget *_window = nullptr;
   GtkWidget *_graph_frame;
-  GtkWidget *_graph_window;
+  GtkWidget *_graph_window = nullptr;
   GtkWidget *_graph_hbox;
   GtkWidget *_graph_vbox;
   GtkWidget *_hpaned;
-  GtkWidget *_scale_area;
+  GtkWidget *_scale_area = nullptr;
   GtkStatsLabelStack _label_stack;
 
   GdkCursor *_hand_cursor;
diff --git a/pandatool/src/pstatserver/pStatFlameGraph.cxx b/pandatool/src/pstatserver/pStatFlameGraph.cxx
index c57d257286..c383994e84 100644
--- a/pandatool/src/pstatserver/pStatFlameGraph.cxx
+++ b/pandatool/src/pstatserver/pStatFlameGraph.cxx
@@ -47,7 +47,6 @@ PStatFlameGraph(PStatMonitor *monitor,
   }
 
   _guide_bar_units = GBU_ms | GBU_hz | GBU_show_units;
-  normal_guide_bars();
 
   monitor->_flame_graphs.insert(this);
 }
@@ -213,8 +212,16 @@ read_datagram(DatagramIterator &scan) {
   PStatGraph::read_datagram(scan);
 
   _current_frame = -1;
-  normal_guide_bars();
+  _stack.clear();
   update();
+  if (_average_mode) {
+    _time_width = _stack.get_net_value(false);
+    if (_time_width == 0.0) {
+      _time_width = 1.0 / pstats_target_frame_rate;
+    }
+    normal_guide_bars();
+    force_redraw();
+  }
 }
 
 /**