diff --git a/libraries/Keyboardio-Macros/src/MacroKeyDefs.h b/libraries/Keyboardio-Macros/src/MacroKeyDefs.h
index 9efa9481..c96f5a4c 100644
--- a/libraries/Keyboardio-Macros/src/MacroKeyDefs.h
+++ b/libraries/Keyboardio-Macros/src/MacroKeyDefs.h
@@ -1,6 +1,6 @@
 #pragma once
 
-#define IS_MACRO       B00000001
+#define IS_MACRO       B00000100
 
 #define M(n)           (Key){ KEY_FLAGS|SYNTHETIC|IS_MACRO, n}
 #define Key_macroKey1  M(1)
diff --git a/libraries/Keyboardio-MouseKeys/src/MouseKeyDefs.h b/libraries/Keyboardio-MouseKeys/src/MouseKeyDefs.h
index b8479b27..3e0951d7 100644
--- a/libraries/Keyboardio-MouseKeys/src/MouseKeyDefs.h
+++ b/libraries/Keyboardio-MouseKeys/src/MouseKeyDefs.h
@@ -1,6 +1,6 @@
 #pragma once
 
-#define IS_MOUSE_KEY     		   B00010000
+#define IS_MOUSE_KEY     		   B00000010
 
 // Synthetic, not internal
 #define KEY_MOUSE_BTN_L 0x01 // Synthetic key
diff --git a/src/key_defs.h b/src/key_defs.h
index 3d8ee3e4..f76a716f 100644
--- a/src/key_defs.h
+++ b/src/key_defs.h
@@ -19,7 +19,8 @@ typedef union {
 #define RALT_HELD         B00000100
 #define SHIFT_HELD        B00001000
 #define GUI_HELD          B00010000
-#define SYNTHETIC         B10000000
+#define SYNTHETIC         B01000000
+#define RESERVED          B10000000
 
 #define LCTRL(k)  ((Key) { k.flags | CTRL_HELD, k.rawKey })
 #define LALT(k)   ((Key) { k.flags | LALT_HELD, k.rawKey })
@@ -28,16 +29,15 @@ typedef union {
 #define LGUI(k)   ((Key) { k.flags | GUI_HELD, k.rawKey })
 
 // we assert that synthetic keys can never have keys held, so we reuse the _HELD bits
-#define IS_SYSCTL        B00000010
-#define IS_CONSUMER      B00000100
-#define IS_INTERNAL      B00001000
-#define SWITCH_TO_KEYMAP 		   B00100000
-#define SWITCH_TO_KEYMAP_MOMENTARY         B01000000
-
+#define IS_SYSCTL                  B00000001
+#define IS_CONSUMER                B00000010
+#define SWITCH_TO_KEYMAP 		       B00000100
+#define SWITCH_TO_KEYMAP_MOMENTARY B00001000
+#define IS_INTERNAL                B00010000
 
 // IS_INTERNAL key table:
 
-#define LED_TOGGLE  0x01 // Synthetic, internal
+#define LED_TOGGLE   B00000001 // Synthetic, internal
 
 
 #define KEYMAP_0     0
@@ -253,4 +253,4 @@ typedef union {
 
 
 
-#define Key_LEDEffectNext (Key) { KEY_FLAGS | SYNTHETIC | IS_INTERNAL, LED_TOGGLE }
+#define Key_LEDEffectNext (Key) { KEY_FLAGS | SYNTHETIC | IS_INTERNAL | LED_TOGGLE, 0 }
diff --git a/src/key_events.cpp b/src/key_events.cpp
index e2692f3d..dd0e3272 100644
--- a/src/key_events.cpp
+++ b/src/key_events.cpp
@@ -1,18 +1,53 @@
 #include "key_events.h"
 
-void handle_synthetic_key_event(Key mappedKey, uint8_t keyState) {
+static void handle_keymap_key_event(Key keymapEntry, uint8_t keyState) {
+    if (keymapEntry.flags & SWITCH_TO_KEYMAP_MOMENTARY ) {
+        if (key_toggled_on(keyState)) {
+            if ( keymapEntry.rawKey == KEYMAP_NEXT) {
+                temporary_keymap++;
+            } else if ( keymapEntry.rawKey == KEYMAP_PREVIOUS) {
+                temporary_keymap--;
+            } else {
+                temporary_keymap = keymapEntry.rawKey;
+            }
+        }
+        if (key_toggled_off(keyState)) {
+            temporary_keymap = primary_keymap;
+        }
+
+        // switch keymap and stay there
+    } else if (key_toggled_on(keyState)) {
+        temporary_keymap = primary_keymap = keymapEntry.rawKey;
+        Storage.save_primary_keymap(primary_keymap);
+    }
+}
+
+static bool handle_synthetic_key_event(Key mappedKey, uint8_t keyState) {
+    if (mappedKey.flags & RESERVED)
+        return false;
+
+    if (!(mappedKey.flags & SYNTHETIC))
+        return false;
+
     if (!key_toggled_on(keyState))
-        return;
+        return true;
 
-    if (mappedKey.flags & IS_CONSUMER) {
-        ConsumerControl.press(mappedKey.rawKey);
-    } else if (mappedKey.flags & IS_INTERNAL) {
-        if (mappedKey.rawKey == LED_TOGGLE) {
+    if (mappedKey.flags & IS_INTERNAL) {
+        if (mappedKey.flags & LED_TOGGLE) {
             LEDControl.next_mode();
+        } else {
+            return false;
         }
+    } else if (mappedKey.flags & IS_CONSUMER) {
+        ConsumerControl.press(mappedKey.rawKey);
     } else if (mappedKey.flags & IS_SYSCTL) {
         SystemControl.press(mappedKey.rawKey);
+    } else if (mappedKey.flags & SWITCH_TO_KEYMAP ||
+               mappedKey.flags & SWITCH_TO_KEYMAP_MOMENTARY) {
+        // Should not happen, handled elsewhere.
     }
+
+    return true;
 }
 
 custom_handler_t eventHandlers[HOOK_MAX];
@@ -96,26 +131,3 @@ void release_key(Key mappedKey) {
     }
     Keyboard.release(mappedKey.rawKey);
 }
-
-
-void handle_keymap_key_event(Key keymapEntry, uint8_t keyState) {
-    if (keymapEntry.flags & SWITCH_TO_KEYMAP_MOMENTARY ) {
-        if (key_toggled_on(keyState)) {
-            if ( keymapEntry.rawKey == KEYMAP_NEXT) {
-                temporary_keymap++;
-            } else if ( keymapEntry.rawKey == KEYMAP_PREVIOUS) {
-                temporary_keymap--;
-            } else {
-                temporary_keymap = keymapEntry.rawKey;
-            }
-        }
-        if (key_toggled_off(keyState)) {
-            temporary_keymap = primary_keymap;
-        }
-
-        // switch keymap and stay there
-    } else if (key_toggled_on(keyState)) {
-        temporary_keymap = primary_keymap = keymapEntry.rawKey;
-        Storage.save_primary_keymap(primary_keymap);
-    }
-}
diff --git a/src/key_events.h b/src/key_events.h
index 2bc6d799..cfa1faab 100644
--- a/src/key_events.h
+++ b/src/key_events.h
@@ -46,10 +46,8 @@ extern const Key keymaps[][ROWS][COLS];
 void handle_key_event(Key mappedKey, byte row, byte col, uint8_t keyState);
 
 // Internal use
-void handle_synthetic_key_event( Key mappedKey, uint8_t keyState);
 void press_key(Key mappedKey);
 void release_key(Key mappedKey);
-void handle_keymap_key_event(Key keymapEntry, uint8_t keyState);
 bool handle_key_event_default(Key mappedKey, byte row, byte col, uint8_t keyState);
 
 Key lookup_key(byte keymap, byte row, byte col);