diff --git a/desmume/src/mic.cpp b/desmume/src/mic.cpp
index 50ce31f92..ac9368e0a 100644
--- a/desmume/src/mic.cpp
+++ b/desmume/src/mic.cpp
@@ -1,6 +1,6 @@
 /* mic.cpp - this file is part of DeSmuME
  *
- * Copyright (C) 2009 DeSmuME Team
+ * Copyright (C) 2009-2011 DeSmuME Team
  *
  * This file is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -20,37 +20,178 @@
 
 #ifndef WIN32
 
-#include "types.h"
+#include <stdlib.h>
 #include "mic.h"
+#include "NDSSystem.h"
 #include "readwrite.h"
-#include "emufile.h"
 
-static BOOL silence = TRUE;
+#define MIC_NULL_SAMPLE_VALUE 0
+#define MIC_MAX_BUFFER_SAMPLES 320
+#define MIC_BUFFER_SIZE (sizeof(u8) * MIC_MAX_BUFFER_SAMPLES)
+#define NUM_INTERNAL_NOISE_SAMPLES 32
 
-BOOL Mic_Init()
+static u8 *micSampleBuffer = NULL; // Pointer to the internal sample buffer.
+static u8 *micReadPosition = NULL; // Pointer to the read position of the internal sample buffer.
+static u8 *micWritePosition = NULL; // Pointer to the write position of the internal sample buffer.
+static unsigned int micBufferFillCount; // The number of readable samples in the internal sample buffer.
+
+static void Mic_BufferClear(void)
 {
-	return TRUE;
+	if (micSampleBuffer == NULL) {
+		return;
+	}
+
+	memset(micSampleBuffer, MIC_NULL_SAMPLE_VALUE, MIC_BUFFER_SIZE);
+	micReadPosition = micSampleBuffer;
+	micWritePosition = micSampleBuffer;
+	micBufferFillCount = 0;
 }
 
-void Mic_Reset()
+BOOL Mic_Init(void)
 {
+	BOOL result = FALSE;
+
+	u8 *newBuffer = (u8 *)malloc(MIC_BUFFER_SIZE);
+	if (newBuffer == NULL) {
+		return result;
+	}
+
+	micSampleBuffer = newBuffer;
+	Mic_BufferClear();
+	result = TRUE;
+
+	return result;
 }
 
-void Mic_DeInit()
+void Mic_DeInit(void)
 {
+	free(micSampleBuffer);
+	micSampleBuffer = NULL;
 }
 
-u8 Mic_ReadSample()
+void Mic_Reset(void)
 {
-	if (silence)
-		return 0;
+	*micReadPosition = MIC_NULL_SAMPLE_VALUE;
+	micWritePosition = micReadPosition;
+	micBufferFillCount = 0;
+}
 
-	return 150;
+static bool Mic_GetActivate(void)
+{
+	return NDS_getFinalUserInput().mic.micButtonPressed;
+}
+
+static bool Mic_IsBufferFull(void)
+{
+	return (micBufferFillCount >= MIC_MAX_BUFFER_SAMPLES);
+}
+
+static bool Mic_IsBufferEmpty(void)
+{
+	return (micBufferFillCount == 0);
+}
+
+static u8 Mic_DefaultBufferRead(void)
+{
+	u8 theSample = MIC_NULL_SAMPLE_VALUE;
+
+	if (micSampleBuffer == NULL) {
+		return theSample;
+	}
+
+	theSample = *micReadPosition;
+
+	if (Mic_IsBufferEmpty()) {
+		return theSample;
+	}
+
+	micReadPosition++;
+	micBufferFillCount--;
+
+	// Move the pointer back to start if we reach the end of the memory block.
+	if (micReadPosition >= (micSampleBuffer + MIC_BUFFER_SIZE)) {
+		micReadPosition = micSampleBuffer;
+	}
+
+	return theSample;
+}
+
+u8 Mic_ReadSample(void)
+{
+	// All mic modes other than Physical must have the mic hotkey pressed in order
+	// to work.
+	if (CommonSettings.micMode != TCommonSettings::Physical && !Mic_GetActivate()) {
+		return MIC_NULL_SAMPLE_VALUE;
+	}
+
+	return Mic_DefaultBufferRead();
+}
+
+static void Mic_DefaultBufferWrite(u8 theSample)
+{
+	if (micSampleBuffer == NULL || Mic_IsBufferFull()) {
+		return;
+	}
+
+	*micWritePosition = theSample;
+	micWritePosition++;
+	micBufferFillCount++;
+
+	// Move the pointer back to start if we reach the end of the memory block.
+	if (micWritePosition >= (micSampleBuffer + MIC_BUFFER_SIZE)) {
+		micWritePosition = micSampleBuffer;
+	}
+}
+
+static u8 Mic_GenerateInternalNoiseSample(void)
+{
+	const u8 noiseSample[NUM_INTERNAL_NOISE_SAMPLES] =
+	{
+		0xFC, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xF5, 0xFF, 0xFF, 0xFF, 0xFF, 0x8E, 0xFF, 
+		0xF4, 0xE1, 0xBF, 0x9A, 0x71, 0x58, 0x5B, 0x5F, 0x62, 0xC2, 0x25, 0x05, 0x01, 0x01, 0x01, 0x01
+	};
+	static unsigned int i = 0;
+
+	if (++i >= NUM_INTERNAL_NOISE_SAMPLES) {
+		i = 0;
+	}
+
+	return noiseSample[i];
+}
+
+static u8 Mic_GenerateWhiteNoiseSample(void)
+{
+	return (u8)(rand() & 0xFF);
+}
+
+static u8 Mic_GenerateNullSample(void)
+{
+	return MIC_NULL_SAMPLE_VALUE;
 }
 
 void Mic_DoNoise(BOOL noise)
 {
-	silence = !noise;
+	u8 (*generator) (void) = NULL;
+
+	if (micSampleBuffer == NULL) {
+		return;
+	}
+
+	if (!noise) {
+		generator = &Mic_GenerateNullSample;
+	} else if (CommonSettings.micMode == TCommonSettings::InternalNoise) {
+		generator = &Mic_GenerateInternalNoiseSample;
+	} else if (CommonSettings.micMode == TCommonSettings::Random) {
+		generator = &Mic_GenerateWhiteNoiseSample;
+	}
+
+	if (generator == NULL) {
+		return;
+	}
+
+	while (micBufferFillCount < MIC_MAX_BUFFER_SAMPLES) {
+		Mic_DefaultBufferWrite(generator());
+	}
 }
 
 void mic_savestate(EMUFILE* os)
diff --git a/desmume/src/mic.h b/desmume/src/mic.h
index ae85a901b..a7fae7ed5 100644
--- a/desmume/src/mic.h
+++ b/desmume/src/mic.h
@@ -1,6 +1,6 @@
 /* mic.h - this file is part of DeSmuME
  *
- * Copyright (C) 2009 DeSmuME Team
+ * Copyright (C) 2009-2011 DeSmuME Team
  *
  * This file is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -20,8 +20,10 @@
 
 #ifndef MIC_H
 #define MIC_H
+
 #include <iostream>
 #include "emufile.h"
+#include "types.h"
 
 #ifdef WIN32
 static char MicSampleName[256];
@@ -34,12 +36,12 @@ extern int MicDisplay;
 void Mic_DoNoise(BOOL);
 #endif
 
-BOOL Mic_Init();
-void Mic_Reset();
-void Mic_DeInit();
-u8 Mic_ReadSample();
+BOOL Mic_Init(void);
+void Mic_Reset(void);
+void Mic_DeInit(void);
+u8 Mic_ReadSample(void);
 
 void mic_savestate(EMUFILE* os);
 bool mic_loadstate(EMUFILE* is, int size);
 
-#endif
+#endif // MIC_H