diff --git a/Analyser/Dynamic/MultiMachine/Implementation/MultiKeyboardMachine.cpp b/Analyser/Dynamic/MultiMachine/Implementation/MultiKeyboardMachine.cpp
index 42d0c0835..c27794e76 100644
--- a/Analyser/Dynamic/MultiMachine/Implementation/MultiKeyboardMachine.cpp
+++ b/Analyser/Dynamic/MultiMachine/Implementation/MultiKeyboardMachine.cpp
@@ -56,10 +56,12 @@ MultiKeyboardMachine::MultiKeyboard::MultiKeyboard(const std::vector<::KeyboardM
 	}
 }
 
-void MultiKeyboardMachine::MultiKeyboard::set_key_pressed(Key key, char value, bool is_pressed) {
+bool MultiKeyboardMachine::MultiKeyboard::set_key_pressed(Key key, char value, bool is_pressed) {
+	bool was_consumed = false;
 	for(const auto &machine: machines_) {
-		machine->get_keyboard().set_key_pressed(key, value, is_pressed);
+		was_consumed |= machine->get_keyboard().set_key_pressed(key, value, is_pressed);
 	}
+	return was_consumed;
 }
 
 void MultiKeyboardMachine::MultiKeyboard::reset_all_keys() {
diff --git a/Analyser/Dynamic/MultiMachine/Implementation/MultiKeyboardMachine.hpp b/Analyser/Dynamic/MultiMachine/Implementation/MultiKeyboardMachine.hpp
index a828546fe..bc0803d83 100644
--- a/Analyser/Dynamic/MultiMachine/Implementation/MultiKeyboardMachine.hpp
+++ b/Analyser/Dynamic/MultiMachine/Implementation/MultiKeyboardMachine.hpp
@@ -32,7 +32,7 @@ class MultiKeyboardMachine: public KeyboardMachine::Machine {
 			public:
 				MultiKeyboard(const std::vector<::KeyboardMachine::Machine *> &machines);
 
-				void set_key_pressed(Key key, char value, bool is_pressed) final;
+				bool set_key_pressed(Key key, char value, bool is_pressed) final;
 				void reset_all_keys() final;
 				const std::set<Key> &observed_keys() final;
 				bool is_exclusive() final;
diff --git a/Inputs/Keyboard.cpp b/Inputs/Keyboard.cpp
index 6193a5ff8..7c9ff819d 100644
--- a/Inputs/Keyboard.cpp
+++ b/Inputs/Keyboard.cpp
@@ -19,14 +19,15 @@ Keyboard::Keyboard(const std::set<Key> &essential_modifiers) : essential_modifie
 Keyboard::Keyboard(const std::set<Key> &observed_keys, const std::set<Key> &essential_modifiers) :
 	observed_keys_(observed_keys), essential_modifiers_(essential_modifiers), is_exclusive_(false) {}
 
-void Keyboard::set_key_pressed(Key key, char value, bool is_pressed) {
+bool Keyboard::set_key_pressed(Key key, char value, bool is_pressed) {
 	std::size_t key_offset = static_cast<std::size_t>(key);
 	if(key_offset >= key_states_.size()) {
 		key_states_.resize(key_offset+1, false);
 	}
 	key_states_[key_offset] = is_pressed;
 
-	if(delegate_) delegate_->keyboard_did_change_key(this, key, is_pressed);
+	if(delegate_) return delegate_->keyboard_did_change_key(this, key, is_pressed);
+	return false;
 }
 
 const std::set<Inputs::Keyboard::Key> &Keyboard::get_essential_modifiers() {
diff --git a/Inputs/Keyboard.hpp b/Inputs/Keyboard.hpp
index 28e5054f1..3011ed826 100644
--- a/Inputs/Keyboard.hpp
+++ b/Inputs/Keyboard.hpp
@@ -45,7 +45,9 @@ class Keyboard {
 		Keyboard(const std::set<Key> &observed_keys, const std::set<Key> &essential_modifiers);
 
 		// Host interface.
-		virtual void set_key_pressed(Key key, char value, bool is_pressed);
+
+		/// @returns @c true if the key press affects the machine; @c false otherwise.
+		virtual bool set_key_pressed(Key key, char value, bool is_pressed);
 		virtual void reset_all_keys();
 
 		/// @returns a set of all Keys that this keyboard responds to.
@@ -68,7 +70,7 @@ class Keyboard {
 
 		// Delegate interface.
 		struct Delegate {
-			virtual void keyboard_did_change_key(Keyboard *keyboard, Key key, bool is_pressed) = 0;
+			virtual bool keyboard_did_change_key(Keyboard *keyboard, Key key, bool is_pressed) = 0;
 			virtual void reset_all_keys(Keyboard *keyboard) = 0;
 		};
 		void set_delegate(Delegate *delegate);
diff --git a/Machines/AmstradCPC/Keyboard.cpp b/Machines/AmstradCPC/Keyboard.cpp
index 8b49d9d61..8850f52ed 100644
--- a/Machines/AmstradCPC/Keyboard.cpp
+++ b/Machines/AmstradCPC/Keyboard.cpp
@@ -13,7 +13,9 @@ using namespace AmstradCPC;
 uint16_t KeyboardMapper::mapped_key_for_key(Inputs::Keyboard::Key key) {
 #define BIND(source, dest)	case Inputs::Keyboard::Key::source:	return dest
 	switch(key) {
-		default: return KeyCopy;
+		default: break;
+
+		BIND(BackTick, KeyCopy);
 
 		BIND(k0, Key0);		BIND(k1, Key1);		BIND(k2, Key2);		BIND(k3, Key3);		BIND(k4, Key4);
 		BIND(k5, Key5);		BIND(k6, Key6);		BIND(k7, Key7);		BIND(k8, Key8);		BIND(k9, Key9);
@@ -72,6 +74,7 @@ uint16_t KeyboardMapper::mapped_key_for_key(Inputs::Keyboard::Key key) {
 		BIND(KeypadDelete, KeyDelete);
 	}
 #undef BIND
+	return KeyboardMachine::MappedMachine::KeyNotMapped;
 }
 
 uint16_t *CharacterMapper::sequence_for_character(char character) {
@@ -142,7 +145,7 @@ uint16_t *CharacterMapper::sequence_for_character(char character) {
 		/* x */		KEYS(KeyX),					/* y */		KEYS(KeyY),
 		/* z */		KEYS(KeyZ),					/* { */		X,
 		/* | */		SHIFT(KeyAt),				/* } */		X,
-		/* ~ */		X,							/* DEL */	KEYS(KeyDelete),
+		/* ~ */		X
 	};
 #undef KEYS
 #undef SHIFT
diff --git a/Machines/Apple/AppleII/AppleII.cpp b/Machines/Apple/AppleII/AppleII.cpp
index 0e1a3c037..3c6c25c44 100644
--- a/Machines/Apple/AppleII/AppleII.cpp
+++ b/Machines/Apple/AppleII/AppleII.cpp
@@ -811,18 +811,18 @@ template <Analyser::Static::AppleII::Target::Model model> class ConcreteMachine:
 			open_apple_is_pressed_ = closed_apple_is_pressed_ = key_is_down_ = false;
 		}
 
-		void set_key_pressed(Key key, char value, bool is_pressed) final {
+		bool set_key_pressed(Key key, char value, bool is_pressed) final {
 			switch(key) {
 				default: break;
 				case Key::F12:
 					m6502_.set_reset_line(is_pressed);
-				return;
+				return true;
 				case Key::LeftOption:
 					open_apple_is_pressed_ = is_pressed;
-				return;
+				return true;
 				case Key::RightOption:
 					closed_apple_is_pressed_ = is_pressed;
-				return;
+				return true;
 			}
 
 			// If no ASCII value is supplied, look for a few special cases.
@@ -833,7 +833,7 @@ template <Analyser::Static::AppleII::Target::Model model> class ConcreteMachine:
 					case Key::Down:			value = 0x0a;	break;
 					case Key::Up:			value = 0x0b;	break;
 					case Key::Backspace:	value = 0x7f;	break;
-					default: return;
+					default: return false;
 				}
 			}
 
@@ -848,6 +848,8 @@ template <Analyser::Static::AppleII::Target::Model model> class ConcreteMachine:
 					key_is_down_ = false;
 				}
 			}
+
+			return true;
 		}
 
 		Inputs::Keyboard &get_keyboard() final {
diff --git a/Machines/Electron/Electron.cpp b/Machines/Electron/Electron.cpp
index 89c6793b8..a9f91d1c0 100644
--- a/Machines/Electron/Electron.cpp
+++ b/Machines/Electron/Electron.cpp
@@ -62,7 +62,7 @@ class ConcreteMachine:
 			set_clock_rate(2000000);
 
 			speaker_.set_input_rate(2000000 / SoundGenerator::clock_rate_divider);
-			speaker_.set_high_frequency_cutoff(7000);
+			speaker_.set_high_frequency_cutoff(6000);
 
 			const std::string machine_name = "Electron";
 			std::vector<ROMMachine::ROM> required_roms = {
diff --git a/Machines/Electron/Keyboard.cpp b/Machines/Electron/Keyboard.cpp
index 1ecd358f4..3ed607ead 100644
--- a/Machines/Electron/Keyboard.cpp
+++ b/Machines/Electron/Keyboard.cpp
@@ -13,7 +13,9 @@ using namespace Electron;
 uint16_t KeyboardMapper::mapped_key_for_key(Inputs::Keyboard::Key key) {
 #define BIND(source, dest)	case Inputs::Keyboard::Key::source:	return Electron::Key::dest
 	switch(key) {
-		default: return KeyCopy;
+		default: break;
+
+		BIND(BackTick, KeyCopy);
 
 		BIND(k0, Key0);		BIND(k1, Key1);		BIND(k2, Key2);		BIND(k3, Key3);		BIND(k4, Key4);
 		BIND(k5, Key5);		BIND(k6, Key6);		BIND(k7, Key7);		BIND(k8, Key8);		BIND(k9, Key9);
@@ -52,6 +54,7 @@ uint16_t KeyboardMapper::mapped_key_for_key(Inputs::Keyboard::Key key) {
 		BIND(Space, KeySpace);
 	}
 #undef BIND
+	return KeyboardMachine::MappedMachine::KeyNotMapped;
 }
 
 uint16_t *CharacterMapper::sequence_for_character(char character) {
@@ -123,7 +126,7 @@ uint16_t *CharacterMapper::sequence_for_character(char character) {
 		/* x */		SHIFT(KeyX),				/* y */		SHIFT(KeyY),
 		/* z */		SHIFT(KeyZ),				/* { */		CTRL(KeyUp),
 		/* | */		SHIFT(KeyRight),			/* } */		CTRL(KeyDown),
-		/* ~ */		CTRL(KeyLeft),				/* DEL */	KEYS(KeyDelete),
+		/* ~ */		CTRL(KeyLeft)
 	};
 #undef KEYS
 #undef SHIFT
diff --git a/Machines/KeyboardMachine.cpp b/Machines/KeyboardMachine.cpp
index 0d79387ee..1a60103d6 100644
--- a/Machines/KeyboardMachine.cpp
+++ b/Machines/KeyboardMachine.cpp
@@ -14,9 +14,11 @@ MappedMachine::MappedMachine(const std::set<Inputs::Keyboard::Key> &essential_mo
 	keyboard_.set_delegate(this);
 }
 
-void MappedMachine::keyboard_did_change_key(Inputs::Keyboard *keyboard, Inputs::Keyboard::Key key, bool is_pressed) {
+bool MappedMachine::keyboard_did_change_key(Inputs::Keyboard *keyboard, Inputs::Keyboard::Key key, bool is_pressed) {
 	uint16_t mapped_key = get_keyboard_mapper()->mapped_key_for_key(key);
-	if(mapped_key != KeyNotMapped) set_key_state(mapped_key, is_pressed);
+	if(mapped_key == KeyNotMapped) return false;
+	set_key_state(mapped_key, is_pressed);
+	return true;
 }
 
 void MappedMachine::reset_all_keys(Inputs::Keyboard *keyboard) {
diff --git a/Machines/KeyboardMachine.hpp b/Machines/KeyboardMachine.hpp
index e4af3adb1..a84f53fb0 100644
--- a/Machines/KeyboardMachine.hpp
+++ b/Machines/KeyboardMachine.hpp
@@ -95,7 +95,7 @@ class MappedMachine: public Inputs::Keyboard::Delegate, public Machine {
 		virtual Inputs::Keyboard &get_keyboard() override;
 
 	private:
-		void keyboard_did_change_key(Inputs::Keyboard *keyboard, Inputs::Keyboard::Key key, bool is_pressed) override;
+		bool keyboard_did_change_key(Inputs::Keyboard *keyboard, Inputs::Keyboard::Key key, bool is_pressed) override;
 		void reset_all_keys(Inputs::Keyboard *keyboard) override;
 		Inputs::Keyboard keyboard_;
 };
diff --git a/Machines/MasterSystem/MasterSystem.cpp b/Machines/MasterSystem/MasterSystem.cpp
index ce98a0bf8..ea4d46cfb 100644
--- a/Machines/MasterSystem/MasterSystem.cpp
+++ b/Machines/MasterSystem/MasterSystem.cpp
@@ -355,12 +355,18 @@ class ConcreteMachine:
 			return keyboard_;
 		}
 
-		void keyboard_did_change_key(Inputs::Keyboard *, Inputs::Keyboard::Key key, bool is_pressed) final {
+		bool keyboard_did_change_key(Inputs::Keyboard *, Inputs::Keyboard::Key key, bool is_pressed) final {
 			if(key == Inputs::Keyboard::Key::Enter) {
 				pause_is_pressed_ = is_pressed;
-			} else if(key == Inputs::Keyboard::Key::Escape) {
-				reset_is_pressed_ = is_pressed;
+				return true;
 			}
+
+			if(key == Inputs::Keyboard::Key::Escape) {
+				reset_is_pressed_ = is_pressed;
+				return true;
+			}
+
+			return false;
 		}
 
 		void reset_all_keys(Inputs::Keyboard *) final {
diff --git a/Machines/ZX8081/Keyboard.cpp b/Machines/ZX8081/Keyboard.cpp
index 5dac570e4..2a0291d65 100644
--- a/Machines/ZX8081/Keyboard.cpp
+++ b/Machines/ZX8081/Keyboard.cpp
@@ -32,6 +32,11 @@ uint16_t KeyboardMapper::mapped_key_for_key(Inputs::Keyboard::Key key) {
 		// Virtual keys follow.
 		BIND(Backspace, KeyDelete);
 		BIND(Escape, KeyBreak);
+		BIND(Up, KeyUp);
+		BIND(Down, KeyDown);
+		BIND(Left, KeyLeft);
+		BIND(Right, KeyRight);
+		BIND(BackTick, KeyEdit);	BIND(F1, KeyEdit);
 	}
 #undef BIND
 	return KeyboardMachine::MappedMachine::KeyNotMapped;
diff --git a/Machines/ZX8081/Keyboard.hpp b/Machines/ZX8081/Keyboard.hpp
index 294787c9b..50fcfeda3 100644
--- a/Machines/ZX8081/Keyboard.hpp
+++ b/Machines/ZX8081/Keyboard.hpp
@@ -26,7 +26,7 @@ enum Key: uint16_t {
 
 	// Add some virtual keys; these do not exist on a real ZX80 or ZX81. They're just a convenience.
 	KeyDelete	= 0x0801,
-	KeyBreak	= 0x0802,
+	KeyBreak, KeyLeft, KeyRight, KeyUp, KeyDown, KeyEdit
 };
 
 struct KeyboardMapper: public KeyboardMachine::MappedMachine::KeyboardMapper {
diff --git a/Machines/ZX8081/ZX8081.cpp b/Machines/ZX8081/ZX8081.cpp
index 8afde474e..9b773e9ec 100644
--- a/Machines/ZX8081/ZX8081.cpp
+++ b/Machines/ZX8081/ZX8081.cpp
@@ -353,19 +353,22 @@ template<bool is_zx81> class ConcreteMachine:
 			const auto line = key >> 8;
 
 			// Check for special cases.
-			if(line == 8) {
+			if(line > 7) {
 				switch(key) {
-					case KeyDelete:
-						// Map delete to shift+0.
-						set_key_state(KeyShift, is_pressed);
-						set_key_state(Key0, is_pressed);
+#define ShiftedKey(source, base)	\
+					case source:	\
+						set_key_state(KeyShift, is_pressed);	\
+						set_key_state(base, is_pressed);		\
 					break;
 
-					case KeyBreak:
-						// Map break to shift+space.
-						set_key_state(KeyShift, is_pressed);
-						set_key_state(KeySpace, is_pressed);
-					break;
+					ShiftedKey(KeyDelete, Key0);
+					ShiftedKey(KeyBreak, KeySpace);
+					ShiftedKey(KeyUp, Key7);
+					ShiftedKey(KeyDown, Key6);
+					ShiftedKey(KeyLeft, Key5);
+					ShiftedKey(KeyRight, Key8);
+					ShiftedKey(KeyEdit, Key1);
+#undef ShiftedKey
 				}
 			} else {
 				if(is_pressed)
diff --git a/OSBindings/Mac/Clock Signal/Machine/CSMachine.mm b/OSBindings/Mac/Clock Signal/Machine/CSMachine.mm
index 35f5dfb81..5992b9fae 100644
--- a/OSBindings/Mac/Clock Signal/Machine/CSMachine.mm	
+++ b/OSBindings/Mac/Clock Signal/Machine/CSMachine.mm	
@@ -504,10 +504,21 @@ struct ActivityObserver: public Activity::Observer {
 				}
 			}
 
-			// If this is logical mode and this key maps to a symbol, supply it
-			// as something to type. If this isn't logical mode, or this key doesn't
-			// map to a symbol, pass it along as a standard press.
-			if(self.inputMode == CSMachineKeyboardInputModeKeyboardLogical) {
+			// Decide whether to try to 'type' (in the logical mapping sense) in the first instance.
+			bool shouldTryToType = self.inputMode == CSMachineKeyboardInputModeKeyboardLogical;
+
+			// Even if the default wasn't to try to type, have a go anyway if the key wasn't
+			// recognised directly. E.g. if the user hits their square bracket key on a machine that
+			// doesn't have a correspondingly-placed key, then try to type a square bracket.
+			if(!shouldTryToType) {
+				@synchronized(self) {
+					shouldTryToType = !keyboard.set_key_pressed(mapped_key, pressedKey, isPressed);
+				}
+			}
+
+			// If this should try to type, give that a go. But typing may fail, e.g. because the user
+			// has pressed something like the cursor keys, which don't actually map to a typeable symbol.
+			if(shouldTryToType) {
 				@synchronized(self) {
 					if(pressedKey && keyboard_machine->can_type(pressedKey)) {
 						if(isPressed) {
@@ -517,10 +528,12 @@ struct ActivityObserver: public Activity::Observer {
 						return;
 					}
 				}
-			}
 
-			@synchronized(self) {
-				keyboard.set_key_pressed(mapped_key, pressedKey, isPressed);
+				// Okay, so at this point either: set_key_pressed was already tried but will fail anyway,
+				// or else it hasn't been tried yet and is worth a go.
+				@synchronized(self) {
+					shouldTryToType = !keyboard.set_key_pressed(mapped_key, pressedKey, isPressed);
+				}
 			}
 
 			return;