queue MIDI sends with delay(1) to avoid race; force legacy advertising

include/app_task.h

@@ -38,6 +38,11 @@ private:
     uint8_t sysex_len = 0;
     bool sysex_active = false;
     
+    bool pending_cc = false;
+    uint8_t pending_channel = 0;
+    uint8_t pending_cc_num = 0;
+    uint8_t pending_value = 0;
+
     void process_switch_event(uint8_t switch_id, bool pressed);
     void run_palette_test();
     void handle_sysex(const uint8_t* data, uint8_t len);

platformio.ini

@@ -18,6 +18,7 @@ build_flags =
     -DARDUINO_USB_CDC_ON_BOOT=1
     -DUSE_TINYUSB=1
     -Wno-macro-redefined
+    -DMYNEWT_VAL_BLE_EXT_ADV=0
 
 monitor_speed = 115200
 

src/app_task.cpp

@@ -49,6 +49,13 @@ void AppTask::update() {
             last_switch_state[i] = false;
         }
     }
+    
+    if (pending_cc) {
+        pending_cc = false;
+        delay(1);
+        usb_midi->send_cc(pending_channel, pending_cc_num, pending_value);
+        if (ble_midi) ble_midi->send_cc(pending_channel, pending_cc_num, pending_value);
+    }
 }
 
 void AppTask::process_midi_event(const MidiEvent& event) {
@@ -136,14 +143,18 @@ void AppTask::process_switch_event(uint8_t switch_id, bool pressed) {
             uint8_t cc_num = cc_map[i];
             uint8_t value = pressed ? 127 : 0;
             
-            if (pressed) {
-                usb_midi->send_cc(channel, cc_num, value);
-                if (ble_midi) ble_midi->send_cc(channel, cc_num, value);
-            }
-            
             Serial.printf("[APP] Switch %d -> Ch%d CC%d Val%d (%s)\n",
                           switch_id, channel, cc_num, value,
                           pressed ? "PRESS" : "RELEASE");
+            
+            if (pressed) {
+                // Send MIDI via a flag that loop() processes
+                pending_cc = true;
+                pending_channel = channel;
+                pending_cc_num = cc_num;
+                pending_value = value;
+            }
+            
             break;
         }
     }