diff --git a/Analyser/Static/Acorn/Target.hpp b/Analyser/Static/Acorn/Target.hpp
index e247f7bfc..c2f9f22b4 100644
--- a/Analyser/Static/Acorn/Target.hpp
+++ b/Analyser/Static/Acorn/Target.hpp
@@ -16,9 +16,9 @@ namespace Static {
 namespace Acorn {
 
 struct Target: public ::Analyser::Static::Target {
-	bool has_adfs;
-	bool has_dfs;
-	bool should_shift_restart;
+	bool has_adfs = false;
+	bool has_dfs = false;
+	bool should_shift_restart = false;
 };
 
 }
diff --git a/Analyser/Static/AmstradCPC/Target.hpp b/Analyser/Static/AmstradCPC/Target.hpp
index 056c45402..795106435 100644
--- a/Analyser/Static/AmstradCPC/Target.hpp
+++ b/Analyser/Static/AmstradCPC/Target.hpp
@@ -22,7 +22,7 @@ struct Target: public ::Analyser::Static::Target {
 		CPC6128
 	};
 
-	Model model;
+	Model model = Model::CPC464;
 };
 
 }
diff --git a/Analyser/Static/Atari/Target.hpp b/Analyser/Static/Atari/Target.hpp
index dc6cd7955..9f0119ada 100644
--- a/Analyser/Static/Atari/Target.hpp
+++ b/Analyser/Static/Atari/Target.hpp
@@ -32,8 +32,8 @@ struct Target: public ::Analyser::Static::Target {
 	};
 
 	// TODO: shouldn't these be properties of the cartridge?
-	PagingModel paging_model;
-	bool uses_superchip;
+	PagingModel paging_model = PagingModel::None;
+	bool uses_superchip = false;
 };
 
 }
diff --git a/Analyser/Static/Commodore/Target.hpp b/Analyser/Static/Commodore/Target.hpp
index 381e35207..b40d0a1f0 100644
--- a/Analyser/Static/Commodore/Target.hpp
+++ b/Analyser/Static/Commodore/Target.hpp
@@ -22,8 +22,8 @@ struct Target: public ::Analyser::Static::Target {
 		ThirtyTwoKB
 	};
 
-	MemoryModel memory_model;
-	bool has_c1540;
+	MemoryModel memory_model = MemoryModel::Unexpanded;
+	bool has_c1540 = false;
 };
 
 }
diff --git a/Analyser/Static/Oric/Target.hpp b/Analyser/Static/Oric/Target.hpp
index b3a507de2..f920d7e5a 100644
--- a/Analyser/Static/Oric/Target.hpp
+++ b/Analyser/Static/Oric/Target.hpp
@@ -14,8 +14,8 @@ namespace Static {
 namespace Oric {
 
 struct Target: public ::Analyser::Static::Target {
-	bool use_atmos_rom;
-	bool has_microdisc;
+	bool use_atmos_rom = false;
+	bool has_microdisc = false;
 };
 
 }
diff --git a/Analyser/Static/ZX8081/Target.hpp b/Analyser/Static/ZX8081/Target.hpp
index 180282576..7fef01e08 100644
--- a/Analyser/Static/ZX8081/Target.hpp
+++ b/Analyser/Static/ZX8081/Target.hpp
@@ -22,8 +22,8 @@ struct Target: public ::Analyser::Static::Target {
 		SixtyFourKB
 	};
 
-	MemoryModel memory_model;
-	bool isZX81;
+	MemoryModel memory_model = MemoryModel::Unexpanded;
+	bool isZX81 = false;
 };
 
 }
diff --git a/Components/6560/6560.hpp b/Components/6560/6560.hpp
index 8cb672d8b..345f67e5f 100644
--- a/Components/6560/6560.hpp
+++ b/Components/6560/6560.hpp
@@ -68,6 +68,10 @@ template <class T> class MOS6560 {
 			set_output_mode(OutputMode::NTSC);
 		}
 
+		~MOS6560() {
+			audio_queue_.flush();
+		}
+
 		void set_clock_rate(double clock_rate) {
 			speaker_.set_input_rate(static_cast<float>(clock_rate / 4.0));
 		}
diff --git a/Concurrency/AsyncTaskQueue.cpp b/Concurrency/AsyncTaskQueue.cpp
index 8775c4309..070301007 100644
--- a/Concurrency/AsyncTaskQueue.cpp
+++ b/Concurrency/AsyncTaskQueue.cpp
@@ -45,6 +45,7 @@ AsyncTaskQueue::AsyncTaskQueue()
 
 AsyncTaskQueue::~AsyncTaskQueue() {
 #ifdef __APPLE__
+	flush();
 	dispatch_release(serial_dispatch_queue_);
 	serial_dispatch_queue_ = nullptr;
 #else
@@ -82,6 +83,7 @@ void AsyncTaskQueue::flush() {
 
 DeferringAsyncTaskQueue::~DeferringAsyncTaskQueue() {
 	perform();
+	flush();
 }
 
 void DeferringAsyncTaskQueue::defer(std::function<void(void)> function) {
diff --git a/Machines/AmstradCPC/AmstradCPC.cpp b/Machines/AmstradCPC/AmstradCPC.cpp
index cd4ca2bff..8a55b8675 100644
--- a/Machines/AmstradCPC/AmstradCPC.cpp
+++ b/Machines/AmstradCPC/AmstradCPC.cpp
@@ -126,6 +126,10 @@ class AYDeferrer {
 			speaker_.set_input_rate(1000000);
 		}
 
+		~AYDeferrer() {
+			audio_queue_.flush();
+		}
+
 		/// Adds @c half_cycles half cycles to the amount of time that has passed.
 		inline void run_for(HalfCycles half_cycles) {
 			cycles_since_update_ += half_cycles;
diff --git a/Machines/Atari2600/Bus.hpp b/Machines/Atari2600/Bus.hpp
index 79d9dfbd4..7d6fabdaf 100644
--- a/Machines/Atari2600/Bus.hpp
+++ b/Machines/Atari2600/Bus.hpp
@@ -26,6 +26,10 @@ class Bus {
 			tia_sound_(audio_queue_),
 			speaker_(tia_sound_) {}
 
+		virtual ~Bus() {
+			audio_queue_.flush();
+		}
+
 		virtual void run_for(const Cycles cycles) = 0;
 		virtual void apply_confidence(Analyser::Dynamic::ConfidenceCounter &confidence_counter) = 0;
 		virtual void set_reset_line(bool state) = 0;
diff --git a/Machines/ColecoVision/ColecoVision.cpp b/Machines/ColecoVision/ColecoVision.cpp
index f238637a3..7acd6ca22 100644
--- a/Machines/ColecoVision/ColecoVision.cpp
+++ b/Machines/ColecoVision/ColecoVision.cpp
@@ -125,6 +125,10 @@ class ConcreteMachine:
 			joysticks_.emplace_back(new Joystick);
 		}
 
+		~ConcreteMachine() {
+			audio_queue_.flush();
+		}
+
 		std::vector<std::unique_ptr<Inputs::Joystick>> &get_joysticks() override {
 			return joysticks_;
 		}
diff --git a/Machines/Electron/Electron.cpp b/Machines/Electron/Electron.cpp
index f54dfe637..edfaaf200 100644
--- a/Machines/Electron/Electron.cpp
+++ b/Machines/Electron/Electron.cpp
@@ -61,6 +61,10 @@ class ConcreteMachine:
 			speaker_.set_input_rate(2000000 / SoundGenerator::clock_rate_divider);
 		}
 
+		~ConcreteMachine() {
+			audio_queue_.flush();
+		}
+
 		void set_rom(ROMSlot slot, const std::vector<uint8_t> &data, bool is_writeable) override final {
 			uint8_t *target = nullptr;
 			switch(slot) {
diff --git a/Machines/MSX/MSX.cpp b/Machines/MSX/MSX.cpp
index cec831d93..aaaa32cc4 100644
--- a/Machines/MSX/MSX.cpp
+++ b/Machines/MSX/MSX.cpp
@@ -144,6 +144,10 @@ class ConcreteMachine:
 			tape_player_.set_sleep_observer(this);
 		}
 
+		~ConcreteMachine() {
+			audio_queue_.flush();
+		}
+
 		void setup_output(float aspect_ratio) override {
 			vdp_.reset(new TI::TMS9918(TI::TMS9918::TMS9918A));
 		}
diff --git a/Machines/Oric/Oric.cpp b/Machines/Oric/Oric.cpp
index 30da85595..64e8e1246 100644
--- a/Machines/Oric/Oric.cpp
+++ b/Machines/Oric/Oric.cpp
@@ -215,6 +215,10 @@ class ConcreteMachine:
 			Memory::Fuzz(ram_, sizeof(ram_));
 		}
 
+		~ConcreteMachine() {
+			audio_queue_.flush();
+		}
+
 		// Obtains the system ROMs.
 		bool set_rom_fetcher(const std::function<std::vector<std::unique_ptr<std::vector<uint8_t>>>(const std::string &machine, const std::vector<std::string> &names)> &roms_with_names) override {
 			auto roms = roms_with_names(
diff --git a/Machines/ZX8081/ZX8081.cpp b/Machines/ZX8081/ZX8081.cpp
index af566af18..ec30e8ebc 100644
--- a/Machines/ZX8081/ZX8081.cpp
+++ b/Machines/ZX8081/ZX8081.cpp
@@ -76,6 +76,10 @@ template<bool is_zx81> class ConcreteMachine:
 			clear_all_keys();
 		}
 
+		~ConcreteMachine() {
+			audio_queue_.flush();
+		}
+
 		forceinline HalfCycles perform_machine_cycle(const CPU::Z80::PartialMachineCycle &cycle) {
 			const HalfCycles previous_counter = horizontal_counter_;
 			horizontal_counter_ += cycle.length;
diff --git a/Processors/Z80/Implementation/Z80Storage.hpp b/Processors/Z80/Implementation/Z80Storage.hpp
index 0ef7244dd..24387224f 100644
--- a/Processors/Z80/Implementation/Z80Storage.hpp
+++ b/Processors/Z80/Implementation/Z80Storage.hpp
@@ -134,9 +134,9 @@ class ProcessorStorage {
 		uint8_t carry_result_;				// the carry flag is set if bit 0 of carry_result_ is set
 		uint8_t halt_mask_ = 0xff;
 
-		int flag_adjustment_history_ = 0;	// a shifting record of whether each opcode set any flags; it turns out
-											// that knowledge of what the last opcode did is necessary to get bits 5 & 3
-											// correct for SCF and CCF.
+		unsigned int flag_adjustment_history_ = 0;	// a shifting record of whether each opcode set any flags; it turns out
+													// that knowledge of what the last opcode did is necessary to get bits 5 & 3
+													// correct for SCF and CCF.
 
 		HalfCycles number_of_cycles_;
 
diff --git a/Storage/Disk/Encodings/MFM/SegmentParser.cpp b/Storage/Disk/Encodings/MFM/SegmentParser.cpp
index 5943fbb0b..8fd0c3810 100644
--- a/Storage/Disk/Encodings/MFM/SegmentParser.cpp
+++ b/Storage/Disk/Encodings/MFM/SegmentParser.cpp
@@ -56,7 +56,7 @@ std::map<std::size_t, Storage::Encodings::MFM::Sector> Storage::Encodings::MFM::
 						case 2:	new_sector->address.sector = shifter.get_byte(); ++position; break;
 						case 3:
 							new_sector->size = shifter.get_byte();
-							size = static_cast<std::size_t>(128 << new_sector->size);
+							size = static_cast<std::size_t>(128 << (new_sector->size&7));
 							++position;
 							is_reading = false;
 							shifter.set_should_obey_syncs(true);