diff --git a/gtk2_ardour/midi_view_background.cc b/gtk2_ardour/midi_view_background.cc
index 91a3a18404..3fa946263e 100644
--- a/gtk2_ardour/midi_view_background.cc
+++ b/gtk2_ardour/midi_view_background.cc
@@ -247,6 +247,10 @@ MidiViewBackground::apply_note_range (uint8_t lowest, uint8_t highest, bool to_c
 		return false;
 	}
 
+	if (lowest == highest) {
+		return false;
+	}
+
 	bool changed = false;
 	uint8_t ol = _lowest_note;
 	uint8_t oh = _highest_note;
@@ -280,9 +284,9 @@ MidiViewBackground::apply_note_range (uint8_t lowest, uint8_t highest, bool to_c
 	int nh = std::min ((int) (UIConfiguration::instance().get_max_note_height() * uiscale), apparent_note_height);
 	int additional_notes = 0;
 
-	if (nh < 3) {
+	if (nh < 1) {
 		/* range does not fit, so center on the data range */
-		nh = 3;
+		nh = 1;
 		range = _data_note_max - _data_note_min;
 		int center = _data_note_min + (range /2);
 		highest = center + ((contents_height() / nh) / 2);
diff --git a/gtk2_ardour/prh_base.cc b/gtk2_ardour/prh_base.cc
index bb72d684d1..618200efcb 100644
--- a/gtk2_ardour/prh_base.cc
+++ b/gtk2_ardour/prh_base.cc
@@ -575,9 +575,9 @@ PianoRollHeaderBase::motion_handler (GdkEventMotion* ev)
 				_saved_top_val  = min (_adj.get_value() + _adj.get_page_size (), 127.0);
 			} else {
 				_saved_top_val = 0.0;
-				// _midi_context.apply_note_range (_adj.get_value (), real_val_at_pointer, true, MidiViewBackground::CanMoveTop);
 				idle_lower = _adj.get_value();
 				idle_upper = real_val_at_pointer;
+				idle_range_move = MidiViewBackground::CanMoveTop;
 				if (!scroomer_drag_connection.connected()) {
 					scroomer_drag_connection = Glib::signal_idle().connect (sigc::mem_fun (*this, &PianoRollHeaderBase::idle_apply_range));
 				}
@@ -587,13 +587,14 @@ PianoRollHeaderBase::motion_handler (GdkEventMotion* ev)
 		case BOTTOM:
 			real_val_at_pointer = real_val_at_pointer >= _saved_bottom_val? _adj.get_value() : real_val_at_pointer;
 			real_val_at_pointer = max (0.0, floor (real_val_at_pointer));
+
 			if (_midi_context.note_height() >= UIConfiguration::instance().get_max_note_height()){
 				_saved_bottom_val  = _adj.get_value();
 			} else {
 				_saved_bottom_val = 127.0;
-				// _midi_context.apply_note_range (real_val_at_pointer, _adj.get_value () + _adj.get_page_size (), true, MidiViewBackground::CanMoveBottom);
+				idle_upper = _adj.get_value() + _adj.get_page_size();
 				idle_lower = real_val_at_pointer;
-				idle_upper = _adj.get_value();
+				idle_range_move = MidiViewBackground::CanMoveBottom;
 				if (!scroomer_drag_connection.connected()) {
 					scroomer_drag_connection = Glib::signal_idle().connect (sigc::mem_fun (*this, &PianoRollHeaderBase::idle_apply_range));
 				}
@@ -648,7 +649,7 @@ PianoRollHeaderBase::motion_handler (GdkEventMotion* ev)
 bool
 PianoRollHeaderBase::idle_apply_range ()
 {
-	_midi_context.apply_note_range (idle_lower, idle_upper, true, MidiViewBackground::CanMoveBottom);
+	_midi_context.apply_note_range (idle_lower, idle_upper, true, idle_range_move);
 	scroomer_drag_connection.disconnect ();
 	return false;
 }
diff --git a/gtk2_ardour/prh_base.h b/gtk2_ardour/prh_base.h
index b0b81500dd..e213a42027 100644
--- a/gtk2_ardour/prh_base.h
+++ b/gtk2_ardour/prh_base.h
@@ -28,6 +28,8 @@
 
 #include <ytkmm/adjustment.h>
 
+#include "midi_view_background.h"
+
 namespace Gdk {
 	class Window;
 }
@@ -37,7 +39,6 @@ namespace ARDOUR {
 }
 
 class MidiView;
-class MidiViewBackground;
 class EditingContext;
 
 class PianoRollHeaderBase : virtual public sigc::trackable {
@@ -149,5 +150,6 @@ class PianoRollHeaderBase : virtual public sigc::trackable {
 	bool idle_apply_range ();
 	double idle_lower;
 	double idle_upper;
+	MidiViewBackground::RangeCanMove idle_range_move;
 	sigc::connection scroomer_drag_connection;
 };