diff --git a/include/led_stub.h b/include/led_stub.h
index 4ee0b3e..3c543fc 100644
--- a/include/led_stub.h
+++ b/include/led_stub.h
@@ -36,6 +36,8 @@ private:
     bool initialized;
     uint32_t activity_off_time = 0;
     uint8_t saved_r = 0, saved_g = 0, saved_b = 0;
+    uint8_t sysex_saved_r[10] = {0}, sysex_saved_g[10] = {0}, sysex_saved_b[10] = {0};
+    bool sysex_flash_active = false;
     uint32_t heartbeat_time = 0;
     uint8_t heartbeat_phase = 0;
     
diff --git a/src/led_stub.cpp b/src/led_stub.cpp
index 654c812..1acbfb2 100644
--- a/src/led_stub.cpp
+++ b/src/led_stub.cpp
@@ -277,43 +277,68 @@ void DefaultLedStub::flash_activity() {
         }
     }
 
-    // Flash ALL LEDs white for SysEx (more visible), LED 0 for regular MIDI
-    for (int i = 0; i < NUM_LEDS; i++) {
-        mux_ptr->set_led_color(i, 255, 255, 255);
-    }
+    // Flash LED 0 white
+    mux_ptr->set_led_color(0, 255, 255, 255);
     mux_ptr->show();
     activity_off_time = now + 50;
 }
 
 void DefaultLedStub::flash_sysex() {
     if (!initialized || !mux_ptr) return;
+    
+    // Save all LED states
+    for (int i = 0; i < NUM_LEDS; i++) {
+        if (led_states[i].active) {
+            uint32_t color = launchpad_palette[led_states[i].velocity];
+            sysex_saved_r[i] = (color >> 16) & 0xFF;
+            sysex_saved_g[i] = (color >> 8) & 0xFF;
+            sysex_saved_b[i] = color & 0xFF;
+        } else {
+            sysex_saved_r[i] = 0;
+            sysex_saved_g[i] = 0;
+            sysex_saved_b[i] = 0;
+        }
+    }
+    
+    // Flash ALL LEDs white
     for (int i = 0; i < NUM_LEDS; i++) {
         mux_ptr->set_led_color(i, 255, 255, 255);
     }
     mux_ptr->show();
-    activity_off_time = millis() + 200;
+    activity_off_time = now + 200;
+    sysex_flash_active = true;
 }
 
 void DefaultLedStub::update() {
     if (!initialized || !mux_ptr) return;
 
-    // Turn off activity flash
     uint32_t now = millis();
+
+    // Turn off activity/SysEx flash
     if (activity_off_time > 0 && now >= activity_off_time) {
-        mux_ptr->set_led_color(0, saved_r, saved_g, saved_b);
+        if (sysex_flash_active) {
+            for (int i = 0; i < NUM_LEDS; i++) {
+                mux_ptr->set_led_color(i, sysex_saved_r[i], sysex_saved_g[i], sysex_saved_b[i]);
+            }
+            sysex_flash_active = false;
+        } else {
+            mux_ptr->set_led_color(0, saved_r, saved_g, saved_b);
+        }
         mux_ptr->show();
         activity_off_time = 0;
     }
 
-    // Heartbeat: pulse LED 9 slowly so we know device is alive
-    if (now - heartbeat_time > 2000) {
+    // Heartbeat: pulse LED 9 slowly (amber)
+    if (now - heartbeat_time > 2000 && !activity_off_time) {
         heartbeat_time = now;
         heartbeat_phase = 1;
     }
-    if (heartbeat_phase) {
+    if (heartbeat_phase && !activity_off_time) {
         uint8_t brightness = (heartbeat_phase < 100) ? (heartbeat_phase * 2) : (400 - heartbeat_phase * 2);
-        mux_ptr->set_led_color(9, brightness, brightness / 4, 0);
-        mux_ptr->show();
+        if (!led_states[9].active) {
+            mux_ptr->set_led_color(9, brightness, brightness / 4, 0);
+            mux_ptr->show();
+        }
         heartbeat_phase++;
         if (heartbeat_phase > 200) heartbeat_phase = 0;
     }