diff --git a/firmware/CMakeLists.txt b/firmware/CMakeLists.txt
index bacffca3e..4e5e1d735 100644
--- a/firmware/CMakeLists.txt
+++ b/firmware/CMakeLists.txt
@@ -28,7 +28,7 @@ set(CHIBIOS_PORTAPACK ${PROJECT_SOURCE_DIR}/chibios-portapack)
 set(HACKRF_FIRMWARE_FILENAME hackrf_one_usb.dfu)
 set(HACKRF_FIRMWARE_IMAGE ${PROJECT_SOURCE_DIR}/${HACKRF_FIRMWARE_FILENAME})
 
-set(HACKRF_CPLD_SVF_FILENAME hackrf_cpld_default.svf)
+set(HACKRF_CPLD_SVF_FILENAME hackrf_cpld_portapack.svf)
 set(HACKRF_CPLD_SVF_PATH ${PROJECT_SOURCE_DIR}/${HACKRF_CPLD_SVF_FILENAME})
 
 set(EXTRACT_CPLD_DATA ${PROJECT_SOURCE_DIR}/tools/extract_cpld_data.py)
diff --git a/firmware/application/analog_audio_app.cpp b/firmware/application/analog_audio_app.cpp
index 57e7183b9..91a682f5f 100644
--- a/firmware/application/analog_audio_app.cpp
+++ b/firmware/application/analog_audio_app.cpp
@@ -66,12 +66,19 @@ NBFMOptionsView::NBFMOptionsView(
 	add_children({
 		&label_config,
 		&options_config,
+		&text_squelch,
+		&field_squelch
 	});
 
 	options_config.set_selected_index(receiver_model.nbfm_configuration());
 	options_config.on_change = [this](size_t n, OptionsField::value_t) {
 		receiver_model.set_nbfm_configuration(n);
 	};
+	
+	field_squelch.set_value(receiver_model.squelch_level());
+	field_squelch.on_change = [this](int32_t v) {
+		receiver_model.set_squelch_level(v);
+	};
 }
 
 /* AnalogAudioView *******************************************************/
diff --git a/firmware/application/analog_audio_app.hpp b/firmware/application/analog_audio_app.hpp
index a82925163..61294e01f 100644
--- a/firmware/application/analog_audio_app.hpp
+++ b/firmware/application/analog_audio_app.hpp
@@ -78,6 +78,19 @@ private:
 			{ "16k ", 0 },
 		}
 	};
+	
+	Text text_squelch {
+		{ 9 * 8, 0 * 16, 7 * 8, 1 * 16 },
+		"SQ    /100"
+	};
+
+	NumberField field_squelch {
+		{ 12 * 8, 0 * 16 },
+		3,
+		{ 0, 100 },
+		1,
+		' ',
+	};
 };
 
 class AnalogAudioView : public View {
diff --git a/firmware/application/baseband_api.cpp b/firmware/application/baseband_api.cpp
index 593068993..f35255f83 100644
--- a/firmware/application/baseband_api.cpp
+++ b/firmware/application/baseband_api.cpp
@@ -52,7 +52,7 @@ void AMConfig::apply() const {
 	audio::set_rate(audio::Rate::Hz_12000);
 }
 
-void NBFMConfig::apply() const {
+void NBFMConfig::apply(const uint8_t squelch_level) const {
 	const NBFMConfigureMessage message {
 		decim_0,
 		decim_1,
@@ -60,7 +60,8 @@ void NBFMConfig::apply() const {
 		2,
 		deviation,
 		audio_24k_hpf_300hz_config,
-		audio_24k_deemph_300_6_config
+		audio_24k_deemph_300_6_config,
+		squelch_level
 	};
 	send_message(&message);
 	audio::set_rate(audio::Rate::Hz_24000);
diff --git a/firmware/application/baseband_api.hpp b/firmware/application/baseband_api.hpp
index e166c56a1..39fb3ee53 100644
--- a/firmware/application/baseband_api.hpp
+++ b/firmware/application/baseband_api.hpp
@@ -48,7 +48,7 @@ struct NBFMConfig {
 	const fir_taps_real<32> channel;
 	const size_t deviation;
 
-	void apply() const;
+	void apply(const uint8_t squelch_level) const;
 };
 
 struct WFMConfig {
diff --git a/firmware/application/receiver_model.cpp b/firmware/application/receiver_model.cpp
index 3392068b9..9b68bbe6f 100644
--- a/firmware/application/receiver_model.cpp
+++ b/firmware/application/receiver_model.cpp
@@ -153,6 +153,15 @@ void ReceiverModel::set_headphone_volume(volume_t v) {
 	update_headphone_volume();
 }
 
+uint8_t ReceiverModel::squelch_level() const {
+	return squelch_level_;
+}
+
+void ReceiverModel::set_squelch_level(uint8_t v) {
+	squelch_level_ = v;
+	update_modulation();
+}
+
 void ReceiverModel::enable() {
 	enabled_ = true;
 	radio::set_direction(rf::Direction::Receive);
@@ -286,7 +295,7 @@ size_t ReceiverModel::nbfm_configuration() const {
 }
 
 void ReceiverModel::update_nbfm_configuration() {
-	nbfm_configs[nbfm_config_index].apply();
+	nbfm_configs[nbfm_config_index].apply(squelch_level_);
 }
 
 size_t ReceiverModel::wfm_configuration() const {
diff --git a/firmware/application/receiver_model.hpp b/firmware/application/receiver_model.hpp
index 1d6d4783c..c3d993d14 100644
--- a/firmware/application/receiver_model.hpp
+++ b/firmware/application/receiver_model.hpp
@@ -71,6 +71,9 @@ public:
 
 	volume_t headphone_volume() const;
 	void set_headphone_volume(volume_t v);
+	
+	uint8_t squelch_level() const;
+	void set_squelch_level(uint8_t v);
 
 	void enable();
 	void disable();
@@ -99,6 +102,7 @@ private:
 	size_t nbfm_config_index = 0;
 	size_t wfm_config_index = 0;
 	volume_t headphone_volume_ { -43.0_dB };
+	uint8_t squelch_level_ { 80 };
 
 	int32_t tuning_offset();
 
diff --git a/firmware/application/ui_scanner.cpp b/firmware/application/ui_scanner.cpp
index 1a75908eb..2a2a93052 100644
--- a/firmware/application/ui_scanner.cpp
+++ b/firmware/application/ui_scanner.cpp
@@ -66,6 +66,14 @@ void ScannerView::do_detection() {
 	rtc::RTC datetime;
 	std::string str_approx, str_timestamp;
 	
+	// Display spectrum
+	bin_skip_acc = 0;
+	pixel_index = 0;
+	display.draw_pixels(
+		{ { 0, 88 }, { (Dim)spectrum_row.size(), 1 } },
+		spectrum_row
+	);
+	
 	mean_power = mean_acc / (SCAN_BIN_NB_NO_DC * slices_nb);
 	mean_acc = 0;
 	
@@ -79,8 +87,8 @@ void ScannerView::do_detection() {
 		
 		if ((power >= mean_power + power_threshold) && (power > power_max)) {
 			power_max = power;
-			bin_max_pixel = slices[slice].max_index;
-			bin_max = bin_max_pixel + (slice * SCAN_BIN_NB);
+			bin_max = slices[slice].max_index + (slice * SCAN_BIN_NB);
+			bin_max_pixel = bin_max / slices_nb;
 		}
 	}
 	
@@ -157,63 +165,65 @@ void ScannerView::do_detection() {
 	scan_counter++;
 	
 	// Refresh red tick
-	portapack::display.fill_rectangle({last_pos, 90, 1, 6}, Color::black());
+	portapack::display.fill_rectangle({last_tick_pos, 90, 1, 6}, Color::black());
 	if (bin_max > -1) {
-		if (bin_max_pixel < 120)
-			bin_max_pixel += 2;
+		//if (bin_max_pixel < 120)
+		//	bin_max_pixel += 2;
 		//else
 		//	bin_max_pixel -= 0;
-		last_pos = (ui::Coord)bin_max_pixel;
-		portapack::display.fill_rectangle({last_pos, 90, 1, 6}, Color::red());
+		last_tick_pos = (Coord)bin_max_pixel;
+		portapack::display.fill_rectangle({last_tick_pos, 90, 1, 6}, Color::red());
 	}
 }
 
+void ScannerView::add_spectrum_pixel(Color color) {
+	// Is avoiding floats really needed ?
+	bin_skip_acc += bin_skip_frac;
+	if (bin_skip_acc < 0x10000) 
+		return;
+	
+	bin_skip_acc -= 0x10000;
+	
+	if (pixel_index < 240)
+		spectrum_row[pixel_index++] = color;
+}
+
 void ScannerView::on_channel_spectrum(const ChannelSpectrum& spectrum) {
-	uint8_t power_max = 0;
-	int16_t bin_max = 0;
+	uint8_t max_power = 0;
+	int16_t max_bin = 0;
 	uint8_t power;
 	size_t bin;
-	std::array<Color, 240> pixel_row;
 	
 	baseband::spectrum_streaming_stop();
 	
-	// Draw spectrum line
+	// Add pixels to spectrum row, and find max power for this slice
+	// Leftmost and rightmost 2 bins are ignored
+	// Center 12 bins are ignored
+	// 256-2-2-12 = 240 bins used
 	for (bin = 0; bin < 120; bin++) {
-		const auto pixel_color = spectrum_rgb3_lut[spectrum.db[134 + bin]];	// 134~253 in 0~119
-		pixel_row[bin] = pixel_color;
-	}
-	for (bin = 120; bin < 240; bin++) {
-		const auto pixel_color = spectrum_rgb3_lut[spectrum.db[bin - 118]];	// 2~121 in 120~239
-		pixel_row[bin] = pixel_color;
-	}
-	display.draw_pixels(
-		{ { 0, 88 + slice_counter * 2 }, { pixel_row.size(), 1 } },
-		pixel_row
-	);
-	
-	// Find max power for this slice
-	for (bin = 0 ; bin < 120; bin++) {
+		add_spectrum_pixel(spectrum_rgb3_lut[spectrum.db[134 + bin]]);	// 134~253 goes in 0~119
 		power = spectrum.db[134 + bin];
 		mean_acc += power;
-		if (power > power_max) {
-			power_max = power;
-			bin_max = bin - 2;
+		if (power > max_power) {
+			max_power = power;
+			max_bin = bin - 2;	// To check
 		}
 	}
 	for (bin = 120; bin < 240; bin++) {
+		add_spectrum_pixel(spectrum_rgb3_lut[spectrum.db[bin - 118]]);	// 2~121 goes in 120~239
 		power = spectrum.db[bin - 118];
 		mean_acc += power;
-		if (power > power_max) {
-			power_max = power;
-			bin_max = bin + 2;
+		if (power > max_power) {
+			max_power = power;
+			max_bin = bin + 2;	// To check
 		}
 	}
 	
-	slices[slice_counter].max_power = power_max;
-	slices[slice_counter].max_index = bin_max;
+	slices[slice_counter].max_power = max_power;
+	slices[slice_counter].max_index = max_bin;
 	
-	// Slice update
 	if (slices_nb > 1) {
+		// Slice sequence
 		slice_counter++;
 		if (slice_counter >= slices_nb) {
 			do_detection();
@@ -221,6 +231,7 @@ void ScannerView::on_channel_spectrum(const ChannelSpectrum& spectrum) {
 		}
 		receiver_model.set_tuning_frequency(slices[slice_counter].center_frequency);
 	} else {
+		// Unique slice
 		do_detection();
 	}
 	
@@ -272,6 +283,8 @@ void ScannerView::on_range_changed() {
 		slices_nb = 1;
 		text_slices.set(" 1");
 	}
+	
+	bin_skip_frac = 0x10000 / slices_nb;
 
 	slice_counter = 0;
 }
@@ -353,7 +366,7 @@ ScannerView::ScannerView(
 		&recent_entries_view
 	});
 	
-	baseband::set_spectrum(SCAN_SLICE_WIDTH, 32);
+	baseband::set_spectrum(SCAN_SLICE_WIDTH, 31);
 	
 	recent_entries_view.set_parent_rect({ 0, 28 * 8, 240, 12 * 8 });
 	recent_entries_view.on_select = [this, &nav](const ScannerRecentEntry& entry) {
diff --git a/firmware/application/ui_scanner.hpp b/firmware/application/ui_scanner.hpp
index 3e84f470a..4cf967027 100644
--- a/firmware/application/ui_scanner.hpp
+++ b/firmware/application/ui_scanner.hpp
@@ -112,6 +112,9 @@ private:
 		int16_t index;
 	} slices[32];
 	
+	uint32_t bin_skip_acc { 0 }, bin_skip_frac { };
+	uint32_t pixel_index { 0 };
+	std::array<Color, 240> spectrum_row { 0 };
 	ChannelSpectrumFIFO* fifo { nullptr };
 	rf::Frequency f_min { 0 }, f_max { 0 };
 	uint8_t detect_timer { 0 }, release_timer { 0 }, timing_div { 0 };
@@ -123,7 +126,7 @@ private:
 	uint8_t slices_nb { 0 };
 	uint8_t slice_counter { 0 };
 	int16_t last_bin { 0 };
-	Coord last_pos { 0 };
+	Coord last_tick_pos { 0 };
 	rf::Frequency scan_span { 0 }, resolved_frequency { 0 };
 	uint16_t locked_bin { 0 };
 	uint8_t scan_counter { 0 };
@@ -135,6 +138,7 @@ private:
 	void on_lna_changed(int32_t v_db);
 	void on_vga_changed(int32_t v_db);
 	void do_timers();
+	void add_spectrum_pixel(Color color);
 	
 	const RecentEntriesColumns columns { {
 		{ "Frequency", 9 },
@@ -149,7 +153,7 @@ private:
 		{ { 1 * 8, 4 * 8 }, "Trig:   /255    Mean:   /255", Color::light_grey() },
 		{ { 1 * 8, 6 * 8 }, "Slices:  /32      Rate:   Hz", Color::light_grey() },
 		{ { 6 * 8, 10 * 8 }, "Timer  Status", Color::light_grey() },
-		{ { 1 * 8, 25 * 8 }, "Accuracy: +/-4.9kHz", Color::light_grey() },
+		{ { 1 * 8, 25 * 8 }, "Accuracy +/-4.9kHz", Color::light_grey() },
 		{ { 26 * 8, 25 * 8 }, "MHz", Color::light_grey() }
 	};
 	 
@@ -188,12 +192,12 @@ private:
 	
 	VuMeter vu_max {
 		{ 1 * 8, 11 * 8 - 4, 3 * 8, 48 },
-		16,
+		18,
 		false
 	};
 	
 	ProgressBar progress_timers {
-		{ 6 * 8, 12 * 8, 5 * 8, 16 }
+		{ 6 * 8, 12 * 8, 6 * 8, 16 }
 	};
 	Text text_infos {
 		{ 13 * 8, 12 * 8, 15 * 8, 16 },
@@ -203,11 +207,11 @@ private:
 	Checkbox check_snap {
 		{ 6 * 8, 15 * 8 },
 		7,
-		"Adjust:",
+		"Snap to:",
 		true
 	};
 	OptionsField options_snap {
-		{ 15 * 8, 15 * 8 },
+		{ 17 * 8, 15 * 8 },
 		7,
 		{
 			{ "25kHz  ", 25000 },
diff --git a/firmware/baseband/proc_nfm_audio.cpp b/firmware/baseband/proc_nfm_audio.cpp
index b25b13a8d..ecd609961 100644
--- a/firmware/baseband/proc_nfm_audio.cpp
+++ b/firmware/baseband/proc_nfm_audio.cpp
@@ -112,8 +112,7 @@ void NarrowbandFMAudio::configure(const NBFMConfigureMessage& message) {
 	channel_filter_pass_f = message.channel_filter.pass_frequency_normalized * channel_filter_input_fs;
 	channel_filter_stop_f = message.channel_filter.stop_frequency_normalized * channel_filter_input_fs;
 	channel_spectrum.set_decimation_factor(std::floor(channel_filter_output_fs / (channel_filter_pass_f + channel_filter_stop_f)));
-	// TODO: Configurable squelch threshold
-	audio_output.configure(message.audio_hpf_config, message.audio_deemph_config, 0.8f);
+	audio_output.configure(message.audio_hpf_config, message.audio_deemph_config, (float)message.squelch_level / 100.0);
 	
 	synth_acc = 0;
 	
diff --git a/firmware/baseband/proc_wideband_spectrum.cpp b/firmware/baseband/proc_wideband_spectrum.cpp
index f17ec245c..2251572e1 100644
--- a/firmware/baseband/proc_wideband_spectrum.cpp
+++ b/firmware/baseband/proc_wideband_spectrum.cpp
@@ -23,8 +23,6 @@
 
 #include "event_m4.hpp"
 
-#include "dsp_fft.hpp"
-
 #include <cstdint>
 #include <cstddef>
 
diff --git a/firmware/common/message.hpp b/firmware/common/message.hpp
index c1988d5ac..ca28fbf7a 100644
--- a/firmware/common/message.hpp
+++ b/firmware/common/message.hpp
@@ -356,7 +356,8 @@ public:
 		const size_t channel_decimation,
 		const size_t deviation,
 		const iir_biquad_config_t audio_hpf_config,
-		const iir_biquad_config_t audio_deemph_config
+		const iir_biquad_config_t audio_deemph_config,
+		const uint8_t squelch_level
 	) : Message { ID::NBFMConfigure },
 		decim_0_filter(decim_0_filter),
 		decim_1_filter(decim_1_filter),
@@ -364,7 +365,8 @@ public:
 		channel_decimation { channel_decimation },
 		deviation { deviation },
 		audio_hpf_config(audio_hpf_config),
-		audio_deemph_config(audio_deemph_config)
+		audio_deemph_config(audio_deemph_config),
+		squelch_level(squelch_level)
 	{
 	}
 
@@ -375,6 +377,7 @@ public:
 	const size_t deviation;
 	const iir_biquad_config_t audio_hpf_config;
 	const iir_biquad_config_t audio_deemph_config;
+	const uint8_t squelch_level;
 };
 
 class WFMConfigureMessage : public Message {
diff --git a/firmware/common/ui_widget.cpp b/firmware/common/ui_widget.cpp
index 1fe80a50f..4941c7102 100644
--- a/firmware/common/ui_widget.cpp
+++ b/firmware/common/ui_widget.cpp
@@ -1461,7 +1461,7 @@ VuMeter::VuMeter(
 	show_max_ { show_max }
 {
 	//set_focusable(false);
-	LED_height = parent_rect.size().height() / LEDs;
+	LED_height = std::max(1UL, parent_rect.size().height() / LEDs);
 	split = 256 / LEDs;
 }
 
@@ -1507,7 +1507,7 @@ void VuMeter::paint(Painter& painter) {
 			else
 				color = lit ? Color::green() : Color::dark_green();
 			
-			painter.fill_rectangle({ pos.x(), pos.y() + (Coord)(bar * LED_height), width, (Coord)LED_height - 2 }, color);
+			painter.fill_rectangle({ pos.x(), pos.y() + (Coord)(bar * (LED_height + 1)), width, (Coord)LED_height }, color);
 		}
 		prev_value = value_;
 	}