diff --git a/gtk2_ardour/midi_cue_background.cc b/gtk2_ardour/midi_cue_background.cc
index 50097938c4..7ca91d3638 100644
--- a/gtk2_ardour/midi_cue_background.cc
+++ b/gtk2_ardour/midi_cue_background.cc
@@ -42,6 +42,8 @@ CueMidiBackground::set_size (double w, double h)
 	_height = h;
 
 	update_contents_height ();
+
+	HeightChanged (); /* EMIT SIGNAL */
 }
 
 double
diff --git a/gtk2_ardour/midi_cue_editor.cc b/gtk2_ardour/midi_cue_editor.cc
index 94f96f531d..892fe4ae26 100644
--- a/gtk2_ardour/midi_cue_editor.cc
+++ b/gtk2_ardour/midi_cue_editor.cc
@@ -188,6 +188,15 @@ MidiCueEditor::build_canvas ()
 	bg = new CueMidiBackground (data_group);
 	_canvas_viewport->signal_size_allocate().connect (sigc::mem_fun(*this, &MidiCueEditor::canvas_allocate));
 
+	prh = new ArdourCanvas::PianoRollHeader (v_scroll_group, *bg);
+
+	double w, h;
+	prh->size_request (w, h);
+
+	prh->set_position (Duple (0., n_timebars * timebar_height));
+	data_group->set_position (ArdourCanvas::Duple (w, timebar_height * n_timebars));
+	h_scroll_group->set_position (Duple (w, 0.));
+
 	_canvas->set_name ("MidiCueCanvas");
 	_canvas->add_events (Gdk::POINTER_MOTION_HINT_MASK | Gdk::SCROLL_MASK | Gdk::KEY_PRESS_MASK | Gdk::KEY_RELEASE_MASK);
 	_canvas->set_can_focus ();
@@ -317,18 +326,16 @@ MidiCueEditor::set_region (std::shared_ptr<ARDOUR::MidiTrack> t, std::shared_ptr
 	view->set_region (r);
 
 	bg->set_view (view);
-
-	delete prh;
-	prh = new ArdourCanvas::PianoRollHeader (v_scroll_group, *view);
+	prh->set_view (*view);
 
 	double w, h;
 	prh->size_request (w, h);
 
 	/* Move stuff around */
 
-	prh->move (Duple (0., n_timebars * timebar_height));
-	data_group->move (ArdourCanvas::Duple (w, timebar_height * n_timebars));
-	h_scroll_group->move (Duple (w, 0.));
+	prh->set_position (Duple (0., n_timebars * timebar_height));
+	data_group->set_position (ArdourCanvas::Duple (w, timebar_height * n_timebars));
+	h_scroll_group->set_position (Duple (w, 0.));
 
 	/* Compute zoom level to show entire source plus some margin if possible */
 
diff --git a/gtk2_ardour/midi_view_background.cc b/gtk2_ardour/midi_view_background.cc
index 6d582d637f..c359be927c 100644
--- a/gtk2_ardour/midi_view_background.cc
+++ b/gtk2_ardour/midi_view_background.cc
@@ -52,6 +52,8 @@ MidiViewBackground::MidiViewBackground (ArdourCanvas::Item* parent)
 
 	note_range_adjustment.set_page_size(_highest_note - _lowest_note);
 	note_range_adjustment.set_value(_lowest_note);
+	note_range_adjustment.set_lower(0);
+	note_range_adjustment.set_upper(127);
 
 	note_range_adjustment.signal_value_changed().connect(sigc::mem_fun(*this, &MidiViewBackground::note_range_adjustment_changed));
 }
diff --git a/gtk2_ardour/midi_view_background.h b/gtk2_ardour/midi_view_background.h
index adcbb5d3dc..088a641457 100644
--- a/gtk2_ardour/midi_view_background.h
+++ b/gtk2_ardour/midi_view_background.h
@@ -27,6 +27,8 @@
 
 #include <gtkmm/adjustment.h>
 
+#include "pbd/signals.h"
+
 #include "ardour/types.h"
 
 #include "gtkmm2ext/colors.h"
@@ -97,6 +99,9 @@ class MidiViewBackground : public virtual ViewBackground
 	virtual void set_note_highlight (bool) = 0;
 	virtual void record_layer_check (std::shared_ptr<ARDOUR::Region>, samplepos_t) = 0;
 
+	virtual void set_size (double w, double h) {}
+	PBD::Signal0<void> HeightChanged;
+
   protected:
 	bool                      _range_dirty;
 	double                    _range_sum_cache;
diff --git a/gtk2_ardour/prh.cc b/gtk2_ardour/prh.cc
index 23e039ad29..1dacfae315 100644
--- a/gtk2_ardour/prh.cc
+++ b/gtk2_ardour/prh.cc
@@ -31,13 +31,15 @@
 #include "gtkmm2ext/keyboard.h"
 #include "gtkmm2ext/rgb_macros.h"
 
+#include "midi++/midnam_patch.h"
+
 #include "editing.h"
+#include "gui_thread.h"
 #include "midi_view.h"
 #include "midi_view_background.h"
 #include "prh.h"
 #include "editing_context.h"
 #include "ui_config.h"
-#include "midi++/midnam_patch.h"
 
 #include "pbd/i18n.h"
 
@@ -46,11 +48,11 @@ using namespace Gtkmm2ext;
 
 namespace ArdourCanvas {
 
-PianoRollHeader::PianoRollHeader (Item* parent, MidiView& v)
+PianoRollHeader::PianoRollHeader (Item* parent, MidiViewBackground& bg)
 	: Rectangle (parent)
-	, have_note_names (false)
-	, _adj (v.midi_context().note_range_adjustment)
-	, _view (v)
+	, _midi_context (bg)
+	, _adj (_midi_context.note_range_adjustment)
+	, _view (nullptr)
 	, _font_descript ("Sans Bold")
 	, _font_descript_big_c ("Sans")
 	, _font_descript_midnam ("Sans")
@@ -67,6 +69,7 @@ PianoRollHeader::PianoRollHeader (Item* parent, MidiView& v)
 	, _saved_bottom_val (127.0)
 	, _mini_map_display (false)
 	, entered (false)
+	, have_note_names (false)
 {
 	Glib::RefPtr<Pango::Context> context = _canvas->get_pango_context();
 
@@ -76,26 +79,16 @@ PianoRollHeader::PianoRollHeader (Item* parent, MidiView& v)
 	_big_c_layout->set_font_description(_font_descript_big_c);
 	_midnam_layout = Pango::Layout::create (context);
 
-	_adj.set_lower(0);
-	_adj.set_upper(127);
-
-	/* set minimum view range to one octave */
-	//set_min_page_size(12);
-
-	//_adj = v->note_range_adjustment;
-
 	for (int i = 0; i < 128; ++i) {
 		_active_notes[i] = false;
 	}
 
-	_view.midi_context().NoteRangeChanged.connect (sigc::mem_fun (*this, &PianoRollHeader::note_range_changed));
-
-	double w, h;
-	size_request (w, h);
-
-	set (Rect (0., 0., w, h));
+	resize ();
+	bg.HeightChanged.connect (height_connection, MISSING_INVALIDATOR, boost::bind (&PianoRollHeader::resize, this), gui_context());
 
 	/* draw vertical lines on both sides of the rectangle */
+	set_fill (false);
+	set_fill (true);
 	set_outline_color (0x000000ff); /* XXX theme me */
 	set_outline_what (Rectangle::What (Rectangle::LEFT|Rectangle::RIGHT));
 
@@ -103,23 +96,32 @@ PianoRollHeader::PianoRollHeader (Item* parent, MidiView& v)
 }
 
 void
-PianoRollHeader::size_request (double& w, double& h) const
+PianoRollHeader::resize ()
 {
-	h = _view.midi_context().contents_height();
-
-	if (show_scroomer()) {
-		w = 60.f * UIConfiguration::instance().get_ui_scale();
-	} else {
-		w = 20.f * UIConfiguration::instance().get_ui_scale();
-	}
-
-	w += 20.;
+	double w, h;
+	size_request (w, h);
+	set (Rect (0., 0., w, h));
 }
 
 void
-PianoRollHeader::size_allocate (ArdourCanvas::Rect const &r)
+PianoRollHeader::set_view (MidiView& v)
 {
-	_alloc = r;
+	_view = &v;
+	_view->midi_context().NoteRangeChanged.connect (sigc::mem_fun (*this, &PianoRollHeader::note_range_changed));
+}
+
+void
+PianoRollHeader::size_request (double& w, double& h) const
+{
+	h = _midi_context.contents_height();
+
+	if (show_scroomer()) {
+		_scroomer_size = 60.f * UIConfiguration::instance().get_ui_scale();
+	} else {
+		_scroomer_size = 20.f * UIConfiguration::instance().get_ui_scale();
+	}
+
+	w = _scroomer_size +  20.;
 }
 
 bool
@@ -174,7 +176,7 @@ render_rect(Cairo::RefPtr<Cairo::Context> cr, int note, double x[], double y[],
 }
 
 void
-PianoRollHeader::render_scroomer(Cairo::RefPtr<Cairo::Context> cr) const
+PianoRollHeader::render_scroomer (Cairo::RefPtr<Cairo::Context> cr) const
 {
 	double scroomer_top = max (1.0, (1.0 - ((_adj.get_value()+_adj.get_page_size()) / 127.0)) * get().height () );
 	double scroomer_bottom = (1.0 - (_adj.get_value () / 127.0)) * get().height ();
@@ -212,16 +214,20 @@ PianoRollHeader::render_scroomer(Cairo::RefPtr<Cairo::Context> cr) const
 bool
 PianoRollHeader::scroll_handler (GdkEventScroll* ev)
 {
+	if (!_view) {
+		return false;
+	}
+
 	int note_range = _adj.get_page_size ();
 	int note_lower = _adj.get_value ();
 
 	if(ev->state == GDK_SHIFT_MASK){
 		switch (ev->direction) {
 		case GDK_SCROLL_UP: //ZOOM IN
-			_view.apply_note_range (min(note_lower + 1, 127), max(note_lower + note_range - 1,0), true);
+			_view->apply_note_range (min(note_lower + 1, 127), max(note_lower + note_range - 1,0), true);
 			break;
 		case GDK_SCROLL_DOWN: //ZOOM OUT
-			_view.apply_note_range (max(note_lower - 1,0), min(note_lower + note_range + 1, 127), true);
+			_view->apply_note_range (max(note_lower - 1,0), min(note_lower + note_range + 1, 127), true);
 			break;
 		default:
 			return false;
@@ -240,7 +246,7 @@ PianoRollHeader::scroll_handler (GdkEventScroll* ev)
 	}
 
 	Duple evd (canvas_to_item (Duple (ev->x, ev->y)));
-	set_note_highlight (_view.midi_context().y_to_note (evd.y));
+	set_note_highlight (_view->midi_context().y_to_note (evd.y));
 
 	_adj.value_changed ();
 	redraw ();
@@ -251,14 +257,14 @@ PianoRollHeader::scroll_handler (GdkEventScroll* ev)
 void
 PianoRollHeader::get_path (int note, double x[], double y[]) const
 {
-	double y_pos = floor(_view.midi_context().note_to_y(note));
+	double y_pos = floor(_midi_context.note_to_y(note));
 	double note_height;
 	double width = get().width() - 1.0f;
 
 	if (note == 0) {
-		note_height = floor(_view.midi_context().contents_height()) - y_pos;
+		note_height = floor(_midi_context.contents_height()) - y_pos;
 	} else {
-		note_height = _view.midi_context().note_height() <= 3 ? _view.midi_context().note_height() : _view.midi_context().note_height() - 1.f;
+		note_height = _midi_context.note_height() <= 3 ? _midi_context.note_height() : _midi_context.note_height() - 1.f;
 	}
 
 	x[0] = _scroomer_size;
@@ -288,6 +294,10 @@ PianoRollHeader::render (ArdourCanvas::Rect const & area, Cairo::RefPtr<Cairo::C
 
 	Rectangle::render (area, cr);
 
+	/* Setup a cairo translation so that all drawing can be done using item
+	 * coordinate
+	 */
+
 	Duple origin (item_to_window (Duple (0., 0.)));
 
 	cr->save ();
@@ -296,8 +306,8 @@ PianoRollHeader::render (ArdourCanvas::Rect const & area, Cairo::RefPtr<Cairo::C
 	Rect self (get());
 
 	double y1 = max (self.y0, 0.);
-	double y2 = min (self.y1, (ArdourCanvas::Coord) floor(_view.midi_context().contents_height()));
-	double av_note_height = _view.midi_context().note_height();
+	double y2 = min (self.y1, (ArdourCanvas::Coord) floor(_midi_context.contents_height()));
+	double av_note_height = _midi_context.note_height();
 	int bc_height, bc_width;
 
 	//Reduce the frequency of Pango layout resizing
@@ -318,8 +328,8 @@ PianoRollHeader::render (ArdourCanvas::Rect const & area, Cairo::RefPtr<Cairo::C
 
 	_midnam_layout->set_font_description(_font_descript_midnam);
 
-	lowest = max(_view.midi_context().lowest_note(), _view.midi_context().y_to_note(y2));
-	highest = min(_view.midi_context().highest_note(), _view.midi_context().y_to_note(y1));
+	lowest = max(_midi_context.lowest_note(), _midi_context.y_to_note(y2));
+	highest = min(_midi_context.highest_note(), _midi_context.y_to_note(y1));
 
 	if (lowest > 127) {
 		lowest = 0;
@@ -355,7 +365,7 @@ PianoRollHeader::render (ArdourCanvas::Rect const & area, Cairo::RefPtr<Cairo::C
 
 		for (int i = lowest; i <= highest; ++i) {
 			int size_x, size_y;
-			double y = floor(_view.midi_context().note_to_y(i)) - 0.5f;
+			double y = floor(_midi_context.note_to_y(i)) - 0.5f;
 			NoteName const & note (note_names[i]);
 
 			_midnam_layout->set_text (note.name);
@@ -466,19 +476,19 @@ PianoRollHeader::render (ArdourCanvas::Rect const & area, Cairo::RefPtr<Cairo::C
 	   so that the top of the C is shown to maintain visual context
 	 */
 	for (int i = lowest - 5; i <= highest; ++i) {
-		double y = floor(_view.midi_context().note_to_y(i)) - 0.5f;
-		double note_height = i == 0? av_note_height : floor(_view.midi_context().note_to_y(i - 1)) - y;
+		double y = floor(_midi_context.note_to_y(i)) - 0.5f;
+		double note_height = i == 0? av_note_height : floor(_midi_context.note_to_y(i - 1)) - y;
 		oct_rel = i % 12;
 
-		if (oct_rel == 0 || (oct_rel == 7 && _adj.get_page_size() <=10) ) {
+		if (oct_rel == 0 || (oct_rel == 7 && _adj.get_page_size() <=10)) {
 			std::stringstream s;
 
 			int cn = i / 12 - 1;
 
 			if (oct_rel == 0){
-				s << "C" << cn;
-			}else{
-				s << "G" << cn;
+				s << 'C' << cn;
+			} else {
+				s << 'G' << cn;
 			}
 
 			if (av_note_height > 12.0){
@@ -523,8 +533,9 @@ PianoRollHeader::instrument_info_change ()
 	   width.
 	*/
 
-
-	_view.midi_track()->gui_changed ("visible_tracks", (void *) 0); /* EMIT SIGNAL */
+	if (_view) {
+		_view->midi_track()->gui_changed ("visible_tracks", (void *) 0); /* EMIT SIGNAL */
+	}
 
 }
 
@@ -609,28 +620,34 @@ PianoRollHeader::get_note_name (int note)
 bool
 PianoRollHeader::motion_handler (GdkEventMotion* ev)
 {
+	if (!_view) {
+		return false;
+	}
+
 	Duple evd (canvas_to_item (Duple (ev->x, ev->y)));
 
 	if (!_scroomer_drag && ev->x < _scroomer_size){
+
 		Gdk::Cursor m_Cursor;
 		double scroomer_top = max(1.0, (1.0 - ((_adj.get_value()+_adj.get_page_size()) / 127.0)) * get().height());
 		double scroomer_bottom = (1.0 - (_adj.get_value () / 127.0)) * get().height();
 
 		if (evd.y > scroomer_top - 5 && evd.y < scroomer_top + 5){
 			m_Cursor = Gdk::Cursor (Gdk::TOP_SIDE);
-			_view.editing_context().push_canvas_cursor (&m_Cursor);
+			_view->editing_context().push_canvas_cursor (&m_Cursor);
 			_scroomer_state = TOP;
-		}else if (evd.y > scroomer_bottom - 5 && evd.y < scroomer_bottom + 5){
+		} else if (evd.y > scroomer_bottom - 5 && evd.y < scroomer_bottom + 5){
 			m_Cursor = Gdk::Cursor (Gdk::BOTTOM_SIDE);
-			_view.editing_context().push_canvas_cursor (&m_Cursor);
+			_view->editing_context().push_canvas_cursor (&m_Cursor);
 			_scroomer_state = BOTTOM;
-		}else {
+		} else {
 			_scroomer_state = MOVE;
-			_view.editing_context().pop_canvas_cursor ();
+			_view->editing_context().pop_canvas_cursor ();
 		}
 	}
 
 	if (_scroomer_drag){
+
 		double pixel2val = 127.0 / get().height();
 		double delta = _old_y - evd.y;
 		double val_at_pointer = (delta * pixel2val);
@@ -647,30 +664,32 @@ PianoRollHeader::motion_handler (GdkEventMotion* ev)
 			case TOP:
 				real_val_at_pointer = real_val_at_pointer <= _saved_top_val? _adj.get_value() + _adj.get_page_size() : real_val_at_pointer;
 				real_val_at_pointer = min(127.0, real_val_at_pointer);
-				if (_view.midi_context().note_height() >= UIConfiguration::instance().get_max_note_height()){
+				if (_midi_context.note_height() >= UIConfiguration::instance().get_max_note_height()){
 					_saved_top_val  = min(_adj.get_value() + _adj.get_page_size (), 127.0);
 				} else {
 					_saved_top_val = 0.0;
 				}
 				//if we are at largest note size & the user is moving down don't do anything
 				//FIXME we are using a heuristic of 18.5 for max note size, but this changes when track size is small to 19.5?
-				_view.midi_context().apply_note_range (_adj.get_value (), real_val_at_pointer, true);
+				_midi_context.apply_note_range (_adj.get_value (), real_val_at_pointer, true);
 				break;
 			case BOTTOM:
 				real_val_at_pointer = max(0.0, real_val_at_pointer);
 				real_val_at_pointer = real_val_at_pointer >= _saved_bottom_val? _adj.get_value() : real_val_at_pointer;
-				if (_view.midi_context().note_height() >= UIConfiguration::instance().get_max_note_height()){
+				if (_midi_context.note_height() >= UIConfiguration::instance().get_max_note_height()){
 					_saved_bottom_val  = _adj.get_value();
 				} else {
 					_saved_bottom_val = 127.0;
 				}
-				_view.midi_context().apply_note_range (real_val_at_pointer, _adj.get_value () + _adj.get_page_size (), true);
+				_midi_context.apply_note_range (real_val_at_pointer, _adj.get_value () + _adj.get_page_size (), true);
 				break;
 			default:
 				break;
 		}
-	}else{
-		int note = _view.midi_context().y_to_note(evd.y);
+
+	} else {
+
+		int note = _midi_context.y_to_note(evd.y);
 		set_note_highlight (note);
 
 		if (_dragging) {
@@ -700,7 +719,7 @@ PianoRollHeader::motion_handler (GdkEventMotion* ev)
 			}
 		}
 	}
-	_adj.value_changed ();
+
 	redraw ();
 	_old_y = evd.y;
 	//win->process_updates(false);
@@ -711,6 +730,10 @@ PianoRollHeader::motion_handler (GdkEventMotion* ev)
 bool
 PianoRollHeader::button_press_handler (GdkEventButton* ev)
 {
+	if (!_view) {
+		return false;
+	}
+
 	/* Convert canvas-coordinates to item coordinates */
 	Duple evd (canvas_to_item (Duple (ev->x, ev->y)));
 
@@ -719,7 +742,7 @@ PianoRollHeader::button_press_handler (GdkEventButton* ev)
 	if (ev->button == 1 && ev->x <= _scroomer_size){
 
 		if (ev->type == GDK_2BUTTON_PRESS) {
-			_view.set_visibility_note_range (MidiStreamView::ContentsRange, false);
+			_view->set_visibility_note_range (MidiStreamView::ContentsRange, false);
 			return true;
 		}
 
@@ -730,7 +753,7 @@ PianoRollHeader::button_press_handler (GdkEventButton* ev)
 		return true;
 
 	} else {
-		int note = _view.midi_context().y_to_note(evd.y);
+		int note = _midi_context.y_to_note(evd.y);
 		bool tertiary = Keyboard::modifier_state_contains (ev->state, Keyboard::TertiaryModifier);
 		bool primary = Keyboard::modifier_state_contains (ev->state, Keyboard::PrimaryModifier);
 
@@ -777,7 +800,7 @@ PianoRollHeader::button_release_handler (GdkEventButton* ev)
 
 	_scroomer_drag = false;
 
-	int note = _view.midi_context().y_to_note(evd.y);
+	int note = _midi_context.y_to_note(evd.y);
 
 	if (false /*editor().current_mouse_mode() == Editing::MouseRange*/) { //Todo:  this mode is buggy, and of questionable utility anyway
 
@@ -829,7 +852,7 @@ bool
 PianoRollHeader::enter_handler (GdkEventCrossing* ev)
 {
 	Duple evd (canvas_to_item (Duple (ev->x, ev->y)));
-	set_note_highlight (_view.midi_context().y_to_note (evd.y));
+	set_note_highlight (_midi_context.y_to_note (evd.y));
 	entered = true;
 	redraw ();
 	return true;
@@ -839,7 +862,9 @@ bool
 PianoRollHeader::leave_handler (GdkEventCrossing*)
 {
 	if (!_scroomer_drag){
-		_view.editing_context().pop_canvas_cursor ();
+		if (_view) {
+			_view->editing_context().pop_canvas_cursor ();
+		}
 	}
 	invalidate_note_range(_highlighted_note, _highlighted_note);
 
@@ -863,11 +888,11 @@ PianoRollHeader::note_range_changed ()
 void
 PianoRollHeader::invalidate_note_range (int lowest, int highest)
 {
-	lowest = max((int) _view.midi_context().lowest_note(), lowest - 1);
-	highest = min((int) _view.midi_context().highest_note(), highest + 2);
+	lowest = max((int) _midi_context.lowest_note(), lowest - 1);
+	highest = min((int) _midi_context.highest_note(), highest + 2);
 
-	double y      = _view.midi_context().note_to_y (highest);
-	double height = _view.midi_context().note_to_y (lowest - 1) - y;
+	double y      = _midi_context.note_to_y (highest);
+	double height = _midi_context.note_to_y (lowest - 1) - y;
 
 	dynamic_cast<ArdourCanvas::GtkCanvas*>(_canvas)->queue_draw_area (0., floor (y), get().width(), floor (height));
 }
@@ -875,13 +900,17 @@ PianoRollHeader::invalidate_note_range (int lowest, int highest)
 bool
 PianoRollHeader::show_scroomer () const
 {
+	if (!_view) {
+		return false;
+	}
+
 	Editing::NoteNameDisplay nnd = UIConfiguration::instance().get_note_name_display();
 
 	if (nnd == Editing::Never) {
 		return false;
 	}
 
-	switch (_view.editing_context().current_mouse_mode()) {
+	switch (_view->editing_context().current_mouse_mode()) {
 	case Editing::MouseDraw:
 	case Editing::MouseContent:
 		if (nnd == Editing::WithMIDNAM) {
@@ -898,12 +927,16 @@ PianoRollHeader::show_scroomer () const
 void
 PianoRollHeader::send_note_on (uint8_t note)
 {
-	std::shared_ptr<ARDOUR::MidiTrack> track = _view.midi_track ();
+	if (!_view) {
+		return;
+	}
+
+	std::shared_ptr<ARDOUR::MidiTrack> track = _view->midi_track ();
 
 	//cerr << "note on: " << (int) note << endl;
 
 	if (track) {
-		_event[0] = (MIDI_CMD_NOTE_ON | _view.midi_context().get_preferred_midi_channel ());
+		_event[0] = (MIDI_CMD_NOTE_ON | _midi_context.get_preferred_midi_channel ());
 		_event[1] = note;
 		_event[2] = 100;
 
@@ -914,10 +947,14 @@ PianoRollHeader::send_note_on (uint8_t note)
 void
 PianoRollHeader::send_note_off (uint8_t note)
 {
-	std::shared_ptr<ARDOUR::MidiTrack> track = _view.midi_track ();
+	if (!_view) {
+		return;
+	}
+
+	std::shared_ptr<ARDOUR::MidiTrack> track = _view->midi_track ();
 
 	if (track) {
-		_event[0] = (MIDI_CMD_NOTE_OFF | _view.midi_context().get_preferred_midi_channel ());
+		_event[0] = (MIDI_CMD_NOTE_OFF | _midi_context.get_preferred_midi_channel ());
 		_event[1] = note;
 		_event[2] = 100;
 
diff --git a/gtk2_ardour/prh.h b/gtk2_ardour/prh.h
index 7724296a0a..49f0508a09 100644
--- a/gtk2_ardour/prh.h
+++ b/gtk2_ardour/prh.h
@@ -39,12 +39,10 @@ namespace ArdourCanvas {
 
 class PianoRollHeader : public ArdourCanvas::Rectangle {
 public:
-	PianoRollHeader (ArdourCanvas::Item* parent, MidiView&);
+	PianoRollHeader (ArdourCanvas::Item* parent, MidiViewBackground&);
 
 	void size_request (double& w, double& h) const;
-
 	void render (ArdourCanvas::Rect const & area, Cairo::RefPtr<Cairo::Context>) const;
-	void size_allocate (ArdourCanvas::Rect const &);
 
 	void instrument_info_change ();
 
@@ -56,55 +54,14 @@ public:
 	sigc::signal<void,uint8_t> ToggleNoteSelection;
 	sigc::signal<void,uint8_t> ExtendNoteSelection;
 
+	void set_view (MidiView&);
+
 private:
+	MidiViewBackground& _midi_context;
+	Gtk::Adjustment&    _adj;
+	MidiView*           _view;
 
-	bool event_handler (GdkEvent*);
-	bool motion_handler (GdkEventMotion*);
-	bool button_press_handler (GdkEventButton*);
-	bool button_release_handler (GdkEventButton*);
-	bool scroll_handler (GdkEventScroll*);
-	bool enter_handler (GdkEventCrossing*);
-	bool leave_handler (GdkEventCrossing*);
-
-	// void on_size_request(Gtk::Requisition*);
-
-	struct NoteName {
-		std::string name;
-		bool from_midnam;
-	};
-	NoteName note_names[128];
-	bool have_note_names;
-	void set_min_page_size(double page_size);
-	void render_scroomer(Cairo::RefPtr<Cairo::Context>) const;
-	NoteName get_note_name (int note);
-
-	Gtk::Adjustment& _adj;
-
-	PianoRollHeader(const PianoRollHeader&);
-
-	enum ItemType {
-		BLACK_SEPARATOR,
-		BLACK_MIDDLE_SEPARATOR,
-		BLACK,
-		WHITE_SEPARATOR,
-		WHITE_RECT,
-		WHITE_CF,
-		WHITE_EB,
-		WHITE_DGA
-	};
-
-	void invalidate_note_range(int lowest, int highest);
-
-	void get_path(int note, double x[], double y[]) const;
-
-	void send_note_on(uint8_t note);
-	void send_note_off(uint8_t note);
-
-	void reset_clicked_note(uint8_t, bool invalidate = true);
-
-	MidiView& _view;
-
-	uint8_t _event[3];
+	uint8_t             _event[3];
 
 	mutable Glib::RefPtr<Pango::Layout> _layout;
 	mutable Glib::RefPtr<Pango::Layout> _big_c_layout;
@@ -117,7 +74,7 @@ private:
 	uint8_t _clicked_note;
 	double _grab_y;
 	bool _dragging;
-	double _scroomer_size;
+	mutable double _scroomer_size;
 	bool _scroomer_drag;
 	double _old_y;
 	double _fract;
@@ -131,9 +88,46 @@ private:
 	mutable bool _mini_map_display;
 	bool entered;
 
-	bool show_scroomer () const;
+	// void on_size_request(Gtk::Requisition*);
 
-	ArdourCanvas::Rect _alloc;
+	struct NoteName {
+		std::string name;
+		bool from_midnam;
+	};
+	NoteName note_names[128];
+	bool have_note_names;
+	PBD::ScopedConnection height_connection;
+
+	void set_min_page_size (double page_size);
+	void render_scroomer (Cairo::RefPtr<Cairo::Context>) const;
+	NoteName get_note_name (int note);
+
+	bool event_handler (GdkEvent*);
+	bool motion_handler (GdkEventMotion*);
+	bool button_press_handler (GdkEventButton*);
+	bool button_release_handler (GdkEventButton*);
+	bool scroll_handler (GdkEventScroll*);
+	bool enter_handler (GdkEventCrossing*);
+	bool leave_handler (GdkEventCrossing*);
+
+	enum ItemType {
+		BLACK_SEPARATOR,
+		BLACK_MIDDLE_SEPARATOR,
+		BLACK,
+		WHITE_SEPARATOR,
+		WHITE_RECT,
+		WHITE_CF,
+		WHITE_EB,
+		WHITE_DGA
+	};
+
+	void invalidate_note_range (int lowest, int highest);
+	void get_path (int note, double x[], double y[]) const;
+	void send_note_on (uint8_t note);
+	void send_note_off (uint8_t note);
+	void reset_clicked_note (uint8_t, bool invalidate = true);
+	bool show_scroomer () const;
+	void resize ();
 };
 
 }
diff --git a/libs/canvas/ruler.cc b/libs/canvas/ruler.cc
index 57f9f5d696..96f8d9f6d0 100644
--- a/libs/canvas/ruler.cc
+++ b/libs/canvas/ruler.cc
@@ -111,7 +111,7 @@ Ruler::set_second_font_description (Pango::FontDescription fd)
 void
 Ruler::render (Rect const & area, Cairo::RefPtr<Cairo::Context> cr) const
 {
-	std::cerr << whoami() << " ruler render " << _lower << " .. " << _upper << "\n";
+	// std::cerr << whoami() << " ruler render " << _lower << " .. " << _upper << "\n";
 
 	if (_lower == _upper) {
 		/* nothing to draw */