diff --git a/src/lib/platform/OSXMediaKeySimulator.h b/src/lib/platform/OSXMediaKeySimulator.h
index 277778df..c62a19bc 100644
--- a/src/lib/platform/OSXMediaKeySimulator.h
+++ b/src/lib/platform/OSXMediaKeySimulator.h
@@ -18,6 +18,7 @@
 #pragma once
 
 #import <CoreFoundation/CoreFoundation.h>
+#import <Carbon/Carbon.h>
 
 #include "synergy/key_types.h"
 
@@ -25,6 +26,8 @@
 extern "C" {
 #endif
 bool				fakeNativeMediaKey(KeyID id);
+bool				isMediaKeyEvent(CGEventRef event);
+bool				getMediaKeyEventInfo(CGEventRef event, KeyID* keyId, bool* down, bool* isRepeat);
 #if defined(__cplusplus)
 }
 #endif
diff --git a/src/lib/platform/OSXMediaKeySimulator.m b/src/lib/platform/OSXMediaKeySimulator.m
index 646807e3..1106a2ea 100644
--- a/src/lib/platform/OSXMediaKeySimulator.m
+++ b/src/lib/platform/OSXMediaKeySimulator.m
@@ -13,52 +13,40 @@
  */
 
 #import "platform/OSXMediaKeySimulator.h"
-
 #import <Cocoa/Cocoa.h>
+#import <IOKit/hidsystem/ev_keymap.h>
 
 int convertKeyIDToNXKeyType(KeyID id)
 {
-	// hidsystem/ev_keymap.h
-	// NX_KEYTYPE_SOUND_UP			0
-	// NX_KEYTYPE_SOUND_DOWN		1
-	// NX_KEYTYPE_BRIGHTNESS_UP		2
-	// NX_KEYTYPE_BRIGHTNESS_DOWN	3
-	// NX_KEYTYPE_MUTE				7
-	// NX_KEYTYPE_EJECT				14
-	// NX_KEYTYPE_PLAY				16
-	// NX_KEYTYPE_NEXT				17
-	// NX_KEYTYPE_PREVIOUS			18
-	// NX_KEYTYPE_FAST				19
-	// NX_KEYTYPE_REWIND			20
-
 	int type = -1;
+
 	switch (id) {
 	case kKeyAudioUp:
-		type = 0;
+		type = NX_KEYTYPE_SOUND_UP;
 		break;
 	case kKeyAudioDown:
-		type = 1;
+		type = NX_KEYTYPE_SOUND_DOWN;
 		break;
 	case kKeyBrightnessUp:
-		type = 2;
+		type = NX_KEYTYPE_BRIGHTNESS_UP;
 		break;
 	case kKeyBrightnessDown:
-		type = 3;
+		type = NX_KEYTYPE_BRIGHTNESS_DOWN;
 		break;
 	case kKeyAudioMute:
-		type = 7;
+		type = NX_KEYTYPE_MUTE;
 		break;
 	case kKeyEject:
-		type = 14;
+		type = NX_KEYTYPE_EJECT;
 		break;
 	case kKeyAudioPlay:
-		type = 16;
+		type = NX_KEYTYPE_PLAY;
 		break;
 	case kKeyAudioNext:
-		type = 17;
+		type = NX_KEYTYPE_NEXT;
 		break;
 	case kKeyAudioPrev:
-		type = 18;
+		type = NX_KEYTYPE_PREVIOUS;
 		break;
 	default:
 		break;
@@ -67,6 +55,80 @@ int convertKeyIDToNXKeyType(KeyID id)
 	return type;
 }
 
+static KeyID
+convertNXKeyTypeToKeyID(uint32_t const type)
+{
+	KeyID id = 0;
+
+	switch (type) { 
+	case NX_KEYTYPE_SOUND_UP:
+		id = kKeyAudioUp;
+		break;
+	case NX_KEYTYPE_SOUND_DOWN:
+		id = kKeyAudioDown;
+		break;
+	case NX_KEYTYPE_MUTE:
+		id = kKeyAudioMute;
+		break;
+	case NX_KEYTYPE_EJECT:
+		id = kKeyEject;
+		break;
+	case NX_KEYTYPE_PLAY:
+		id = kKeyAudioPlay;
+		break;
+	case NX_KEYTYPE_FAST:
+	case NX_KEYTYPE_NEXT:
+		id = kKeyAudioNext;
+		break;
+	case NX_KEYTYPE_REWIND:
+	case NX_KEYTYPE_PREVIOUS:
+		id = kKeyAudioPrev;
+		break;
+	default:
+		break;
+	}
+
+	return id;
+}
+
+bool
+isMediaKeyEvent(CGEventRef event) {
+	NSEvent* nsEvent = nil;
+	@try {
+		nsEvent = [NSEvent eventWithCGEvent: event];
+		if ([nsEvent subtype] != 8) {
+			return false;
+		}
+		uint32_t const nxKeyId = ([nsEvent data1] & 0xFFFF0000) >> 16;
+		if (convertNXKeyTypeToKeyID (nxKeyId)) {
+			return true;
+		}
+	} @catch (NSException* e) {
+	}
+	return false;
+}
+
+bool
+getMediaKeyEventInfo(CGEventRef event, KeyID* const keyId, 
+					 bool* const down, bool* const isRepeat) {
+	NSEvent* nsEvent = nil;
+	@try {
+		nsEvent = [NSEvent eventWithCGEvent: event];
+	} @catch (NSException* e) {
+		return false;
+	}
+	if (keyId) {
+		*keyId = convertNXKeyTypeToKeyID (([nsEvent data1] & 0xFFFF0000) >> 16);
+	}
+	if (down) {
+		*down = !([nsEvent data1] & 0x100);
+	}
+	if (isRepeat) {
+		*isRepeat = [nsEvent data1] & 0x1;
+	}
+	return true;
+}
+
 bool
 fakeNativeMediaKey(KeyID id)
 {
diff --git a/src/lib/platform/OSXScreen.cpp b/src/lib/platform/OSXScreen.cpp
index 2a4c5c4a..da18190e 100644
--- a/src/lib/platform/OSXScreen.cpp
+++ b/src/lib/platform/OSXScreen.cpp
@@ -25,6 +25,7 @@
 #include "platform/OSXKeyState.h"
 #include "platform/OSXScreenSaver.h"
 #include "platform/OSXDragSimulator.h"
+#include "platform/OSXMediaKeySimulator.h"
 #include "platform/OSXPasteboardPeeker.h"
 #include "synergy/Clipboard.h"
 #include "synergy/KeyMap.h"
@@ -1333,6 +1334,23 @@ OSXScreen::onKey(CGEventRef event)
 	return true;
 }
 
+void
+OSXScreen::onMediaKey(CGEventRef event) 
+{
+	KeyID keyID;
+	bool down;
+	bool isRepeat;
+
+	if (!getMediaKeyEventInfo (event, &keyID, &down, &isRepeat)) {
+		LOG ((CLOG_ERR "Failed to decode media key event"));
+		return;
+	}
+
+	LOG ((CLOG_DEBUG2 "Media key event: keyID=0x%02x, %s, repeat=%s",
+						keyID, (down ? "down": "up"),
+						(isRepeat ? "yes" : "no")));
+}
+
 bool
 OSXScreen::onHotKey(EventRef event) const
 {
@@ -1941,8 +1959,13 @@ OSXScreen::handleCGInputEvent(CGEventTapProxy proxy,
 		case NX_NULLEVENT:
 			break;
 		case NX_SYSDEFINED:
-			LOG((CLOG_DEBUG2 "unknown system defined event"));
-			return event;
+			if (isMediaKeyEvent (event)) {
+				LOG((CLOG_DEBUG2 "detected media key event"));
+				screen->onMediaKey (event);
+			} else {
+				LOG((CLOG_DEBUG2 "ignoring unknown system defined event"));
+				return event;
+			}
 			break;
 		case NX_NUMPROCS:
 			break;
diff --git a/src/lib/platform/OSXScreen.h b/src/lib/platform/OSXScreen.h
index 77a0cedc..dce5ac08 100644
--- a/src/lib/platform/OSXScreen.h
+++ b/src/lib/platform/OSXScreen.h
@@ -128,6 +128,8 @@ private:
 	void				constructMouseButtonEventMap();
 
 	bool				onKey(CGEventRef event);
+
+	void				onMediaKey(CGEventRef event);
 	
 	bool				onHotKey(EventRef event) const;