diff --git a/firmware/baseband/spectrum_collector.hpp b/firmware/baseband/spectrum_collector.hpp
index 6c50120b..b238c1fe 100644
--- a/firmware/baseband/spectrum_collector.hpp
+++ b/firmware/baseband/spectrum_collector.hpp
@@ -35,7 +35,8 @@
 class SpectrumCollector {
 public:
 	constexpr SpectrumCollector(
-	) : channel_spectrum_decimator { 1 }
+	) : channel_spectrum_decimator { 1 },
+		fifo { fifo_data, ChannelSpectrumConfigMessage::fifo_k }
 	{
 	}
 
@@ -52,6 +53,7 @@ public:
 private:
 	BlockDecimator<complex16_t, 256> channel_spectrum_decimator;
 	ChannelSpectrumFIFO fifo;
+	ChannelSpectrum fifo_data[1 << ChannelSpectrumConfigMessage::fifo_k];
 
 	volatile bool channel_spectrum_request_update { false };
 	bool streaming { false };
diff --git a/firmware/common/fifo.hpp b/firmware/common/fifo.hpp
index 86c06a73..56e82baa 100644
--- a/firmware/common/fifo.hpp
+++ b/firmware/common/fifo.hpp
@@ -22,18 +22,24 @@
 #ifndef __FIFO_H__
 #define __FIFO_H__
 
+#include <cstddef>
 #include <algorithm>
 #include <cstring>
+#include <memory>
 
 #include <hal.h>
 
 /* FIFO implementation inspired by Linux kfifo. */
 
-template<typename T, size_t K>
+template<typename T>
 class FIFO {
 public:
 	constexpr FIFO(
-	) : _in { 0 },
+		T* data,
+		size_t k
+	) : _data { data },
+		_size { 1U << k },
+		_in { 0 },
 		_out { 0 }
 	{
 	}
@@ -150,15 +156,15 @@ public:
 	}
 
 private:
-	static constexpr size_t size() {
-		return (1UL << K);
+	size_t size() const {
+		return _size;
 	}
 
 	static constexpr size_t esize() {
 		return sizeof(T);
 	}
 
-	static constexpr size_t mask() {
+	size_t mask() const {
 		return size() - 1;
 	}
 
@@ -224,7 +230,8 @@ private:
 		return buf_len;
 	}
 
-	T _data[size()];
+	T* const _data;
+	const size_t _size;
 	volatile size_t _in;
 	volatile size_t _out;
 };
diff --git a/firmware/common/message.hpp b/firmware/common/message.hpp
index c29eb11e..cbce464e 100644
--- a/firmware/common/message.hpp
+++ b/firmware/common/message.hpp
@@ -244,10 +244,12 @@ struct ChannelSpectrum {
 	uint32_t channel_filter_stop_frequency { 0 };
 };
 
-using ChannelSpectrumFIFO = FIFO<ChannelSpectrum, 2>;
+using ChannelSpectrumFIFO = FIFO<ChannelSpectrum>;
 
 class ChannelSpectrumConfigMessage : public Message {
 public:
+	static constexpr size_t fifo_k = 2;
+	
 	constexpr ChannelSpectrumConfigMessage(
 		ChannelSpectrumFIFO* fifo
 	) : Message { ID::ChannelSpectrumConfig },
diff --git a/firmware/common/message_queue.hpp b/firmware/common/message_queue.hpp
index c4430a23..baba13ef 100644
--- a/firmware/common/message_queue.hpp
+++ b/firmware/common/message_queue.hpp
@@ -32,10 +32,13 @@ using namespace lpc43xx;
 
 #include <ch.h>
 
-template<size_t K>
 class MessageQueue {
 public:
-	MessageQueue() {
+	MessageQueue(
+		uint8_t* const data,
+		size_t k
+	) : fifo { data, k }
+	{
 		chMtxInit(&mutex_write);
 	}
 
@@ -80,7 +83,7 @@ public:
 	}
 
 private:
-	FIFO<uint8_t, K> fifo;
+	FIFO<uint8_t> fifo;
 	Mutex mutex_write;
 
 	bool push(const void* const buf, const size_t len) {
diff --git a/firmware/common/portapack_shared_memory.hpp b/firmware/common/portapack_shared_memory.hpp
index a0fd7010..f7c11d0c 100644
--- a/firmware/common/portapack_shared_memory.hpp
+++ b/firmware/common/portapack_shared_memory.hpp
@@ -23,6 +23,7 @@
 #define __PORTAPACK_SHARED_MEMORY_H__
 
 #include <cstdint>
+#include <cstddef>
 
 #include "message_queue.hpp"
 
@@ -32,8 +33,13 @@ struct TouchADCFrame {
 
 /* NOTE: These structures must be located in the same location in both M4 and M0 binaries */
 struct SharedMemory {
-	MessageQueue<12> baseband_queue;
-	MessageQueue<11> application_queue;
+	static constexpr size_t baseband_queue_k = 12;
+	static constexpr size_t application_queue_k = 11;
+
+	MessageQueue baseband_queue;
+	uint8_t baseband_queue_data[1 << baseband_queue_k];
+	MessageQueue application_queue;
+	uint8_t application_queue_data[1 << application_queue_k];
 
 	// TODO: M0 should directly configure and control DMA channel that is
 	// acquiring ADC samples.
@@ -44,8 +50,12 @@ extern SharedMemory& shared_memory;
 
 #if defined(LPC43XX_M0)
 inline void init_message_queues() {
-	new (&shared_memory.baseband_queue) MessageQueue<12>();
-	new (&shared_memory.application_queue) MessageQueue<11>();
+	new (&shared_memory.baseband_queue) MessageQueue(
+		shared_memory.baseband_queue_data, SharedMemory::baseband_queue_k
+	);
+	new (&shared_memory.application_queue) MessageQueue(
+		shared_memory.application_queue_data, SharedMemory::application_queue_k
+	);
 }
 #endif