diff --git a/Machines/Typer.cpp b/Machines/Typer.cpp
index 5fed58a28..241dc3810 100644
--- a/Machines/Typer.cpp
+++ b/Machines/Typer.cpp
@@ -15,7 +15,7 @@ Typer::Typer(const char *string, int delay, int frequency, Delegate *delegate) :
 		counter_(-delay), frequency_(frequency), string_pointer_(0), delegate_(delegate), phase_(0) {
 	size_t string_size = strlen(string) + 3;
 	string_ = (char *)malloc(string_size);
-	snprintf(string_, strlen(string) + 3, "%c%s%c", Typer::BeginString, string, Typer::EndString);
+	snprintf(string_, string_size, "%c%s%c", Typer::BeginString, string, Typer::EndString);
 }
 
 void Typer::update(int duration) {
diff --git a/Machines/Typer.hpp b/Machines/Typer.hpp
index a94de9438..dc089d4c4 100644
--- a/Machines/Typer.hpp
+++ b/Machines/Typer.hpp
@@ -51,7 +51,6 @@ class TypeRecipient: public Typer::Delegate {
 
 		void typer_reset(Typer *typer) {
 			clear_all_keys();
-			typer_.reset();
 		}
 
 	protected:
diff --git a/Outputs/CRT/CRT.cpp b/Outputs/CRT/CRT.cpp
index 5b4cf0cdc..c5ba7ee68 100644
--- a/Outputs/CRT/CRT.cpp
+++ b/Outputs/CRT/CRT.cpp
@@ -113,7 +113,7 @@ Flywheel::SyncEvent CRT::get_next_horizontal_sync_event(bool hsync_is_requested,
 #define source_output_position_y()	(*(uint16_t *)&next_run[SourceVertexOffsetOfOutputStart + 2])
 #define source_output_position_x2()	(*(uint16_t *)&next_run[SourceVertexOffsetOfEnds + 2])
 #define source_phase()				next_run[SourceVertexOffsetOfPhaseTimeAndAmplitude + 0]
-#define source_amplitude()			next_run[SourceVertexOffsetOfPhaseTimeAndAmplitude + 2]
+#define source_amplitude()			next_run[SourceVertexOffsetOfPhaseTimeAndAmplitude + 1]
 
 void CRT::advance_cycles(unsigned int number_of_cycles, bool hsync_requested, bool vsync_requested, const Scan::Type type) {
 	std::unique_lock<std::mutex> output_lock = openGL_output_builder_.get_output_lock();
diff --git a/Outputs/CRT/Internals/Shaders/IntermediateShader.cpp b/Outputs/CRT/Internals/Shaders/IntermediateShader.cpp
index 670effaeb..4103230a5 100644
--- a/Outputs/CRT/Internals/Shaders/IntermediateShader.cpp
+++ b/Outputs/CRT/Internals/Shaders/IntermediateShader.cpp
@@ -47,7 +47,7 @@ std::unique_ptr<IntermediateShader> IntermediateShader::make_shader(const std::s
 		"uniform float outputVerticalOffset;"
 		"uniform float textureHeightDivisor;"
 
-		"out vec2 phaseAndAmplitudeVarying;"
+		"out vec3 phaseAndAmplitudeVarying;"
 		"out vec2 inputPositionsVarying[11];"
 		"out vec2 iInputPositionVarying;"
 		"out vec2 delayLinePositionVarying;"
@@ -94,9 +94,11 @@ std::unique_ptr<IntermediateShader> IntermediateShader::make_shader(const std::s
 			"delayLinePositionVarying = mappedInputPosition - vec2(0.0, 1.0);"
 
 			// setup phaseAndAmplitudeVarying.x as colour burst subcarrier phase, in radians;
-			// setup phaseAndAmplitudeVarying.x as colour burst amplitude
+			// setup phaseAndAmplitudeVarying.y as colour burst amplitude;
+			// setup phaseAndAmplitudeVarying.z as 1 / (colour burst amplitude), or 0.0 if amplitude is 0.0;
 			"phaseAndAmplitudeVarying.x = (extendedOutputPosition.x + (phaseTimeAndAmplitude.x / 64.0)) * 0.5 * 3.141592654;"
-			"phaseAndAmplitudeVarying.y = 0.33;" // TODO: reinstate connection with (phaseTimeAndAmplitude.y/256.0)
+			"phaseAndAmplitudeVarying.y = phaseTimeAndAmplitude.y / 255.0;"
+			"phaseAndAmplitudeVarying.z = (phaseAndAmplitudeVarying.y > 0.0) ? 1.0 / phaseAndAmplitudeVarying.y : 0.0;"
 
 			// determine output position by scaling the output position according to the texture size
 			"vec2 eyePosition = 2.0*(extendedOutputPosition / outputTextureSize) - vec2(1.0);"
@@ -133,7 +135,7 @@ std::unique_ptr<IntermediateShader> IntermediateShader::make_source_conversion_s
 
 		"in vec2 inputPositionsVarying[11];"
 		"in vec2 iInputPositionVarying;"
-		"in vec2 phaseAndAmplitudeVarying;"
+		"in vec3 phaseAndAmplitudeVarying;"
 
 		"out vec4 fragColour;"
 
@@ -161,7 +163,7 @@ std::unique_ptr<IntermediateShader> IntermediateShader::make_rgb_source_shader(c
 
 		"in vec2 inputPositionsVarying[11];"
 		"in vec2 iInputPositionVarying;"
-		"in vec2 phaseAndAmplitudeVarying;"
+		"in vec3 phaseAndAmplitudeVarying;"
 
 		"out vec3 fragColour;"
 
@@ -185,7 +187,7 @@ std::unique_ptr<IntermediateShader> IntermediateShader::make_chroma_luma_separat
 	return make_shader(
 		"#version 150\n"
 
-		"in vec2 phaseAndAmplitudeVarying;"
+		"in vec3 phaseAndAmplitudeVarying;"
 		"in vec2 inputPositionsVarying[11];"
 
 		"out vec3 fragColour;"
@@ -200,10 +202,10 @@ std::unique_ptr<IntermediateShader> IntermediateShader::make_chroma_luma_separat
 				"texture(texID, inputPositionsVarying[5]).r,"
 				"texture(texID, inputPositionsVarying[6]).r"
 			");"
-			"float luminance = dot(samples, vec4(0.25));"
+			"float luminance = mix(dot(samples, vec4(0.25)), dot(samples, vec4(0.0, 0.16, 0.66, 0.16)), step(phaseAndAmplitudeVarying.z, 0.0));"
 
 			// define chroma to be whatever was here, minus luma
-			"float chrominance = 0.5 * (samples.z - luminance) / phaseAndAmplitudeVarying.y;"
+			"float chrominance = 0.5 * (samples.z - luminance) * phaseAndAmplitudeVarying.z;"
 			"luminance /= (1.0 - phaseAndAmplitudeVarying.y);"
 
 			// split choma colours here, as the most direct place, writing out