Updates for Audio System

Apps/Breakout/main/Source/Breakout.cpp

@@ -124,7 +124,6 @@ void Breakout::onShow(AppHandle appHandle, lv_obj_t* parent) {
     if (!sfxEngine) {
         sfxEngine = new SfxEngine();
         sfxEngine->start();
-        sfxEngine->applyVolumePreset(SfxEngine::VolumePreset::Quiet);
         sfxEngine->setEnabled(soundEnabled);
     }
 

Apps/MediaKeys/main/Source/MediaKeys.cpp

@@ -211,19 +211,49 @@ void MediaKeys::startHid() {
     if (tt_lvgl_hardware_keyboard_is_available()) enterKeyMode();
 }
 
+void MediaKeys::teardownBt() {
+    // Remove callback FIRST - stops any in-flight BT events from firing against
+    // our (possibly already freed) UI widget pointers after this returns.
+    if (_btDevice) bluetooth_remove_event_callback(_btDevice, btEventCallback);
+    // Do NOT call bluetooth_hid_device_stop here: it calls ble_gatts_reset() /
+    // ble_gatts_start() which corrupts NimBLE heap while the host task is still
+    // running. HID device is a persistent kernel device; hid_device_start() cleans
+    // up stale context on next use. Explicit stop is handled by handleSwitchToggle.
+    // Restore the radio/device to the state we found them in.
+    if (_btDevice && _radioWasOff) bluetooth_set_radio_enabled(_btDevice, false);
+    if (_btDevice && _deviceWasStarted) device_stop(_btDevice);
+    _btDevice = nullptr;
+    _hidDevice = nullptr;
+    _radioWasOff = false;
+    _deviceWasStarted = false;
+}
+
 void MediaKeys::handleSwitchToggle(bool enabled) {
     LOG_I(TAG, "Switch: %s", enabled ? "ON" : "OFF");
     _isEnabled = enabled;
 
     if (enabled) {
-        _btDevice = bluetooth_find_first_ready_device();
+        _btDevice = device_find_first_by_type(&BLUETOOTH_TYPE);
         if (!_btDevice) {
             LOG_E(TAG, "No Bluetooth device found");
             _isEnabled = false;
             if (_switchWidget) lv_obj_remove_state(_switchWidget, LV_STATE_CHECKED);
             return;
         }
 
+        // Device may not be started yet (BT disabled in DTS by default to save memory).
+        if (!device_is_ready(_btDevice)) {
+            LOG_I(TAG, "BT device not started, starting now");
+            if (device_start(_btDevice) != ERROR_NONE) {
+                LOG_E(TAG, "Failed to start BT device");
+                _btDevice = nullptr;
+                _isEnabled = false;
+                if (_switchWidget) lv_obj_remove_state(_switchWidget, LV_STATE_CHECKED);
+                return;
+            }
+            _deviceWasStarted = true;
+        }
+
         bluetooth_set_device_name(_btDevice, "Tactility Media Keys");
 
         // Register callback before enabling radio so we don't miss the state-change event.
@@ -247,12 +277,10 @@ void MediaKeys::handleSwitchToggle(bool enabled) {
     } else {
         _radioEnabling = false;
         if (tt_lvgl_hardware_keyboard_is_available()) exitKeyMode();
+        // Explicit user toggle-off: stop HID cleanly (safe here since we're on the
+        // LVGL task and the user intentionally disabled, so no race with app teardown).
         if (_hidDevice) bluetooth_hid_device_stop(_hidDevice);
-        if (_btDevice) bluetooth_remove_event_callback(_btDevice, btEventCallback);
-        if (_btDevice && _radioWasOff) bluetooth_set_radio_enabled(_btDevice, false);
-        _radioWasOff = false;
-        _btDevice = nullptr;
-        _hidDevice = nullptr;
+        teardownBt();
         if (_mainWrapper) lv_obj_add_flag(_mainWrapper, LV_OBJ_FLAG_HIDDEN);
     }
 }
@@ -321,19 +349,23 @@ void MediaKeys::onShow(AppHandle appHandle, lv_obj_t* parent) {
     }
 
     lv_obj_add_flag(_mainWrapper, LV_OBJ_FLAG_HIDDEN);
+
+    // Auto-enable if BT is already on (turned on via QuickPanel/Settings before opening app).
+    struct Device* btDev = device_find_first_by_type(&BLUETOOTH_TYPE);
+    if (btDev && device_is_ready(btDev)) {
+        enum BtRadioState radioState;
+        if (bluetooth_get_radio_state(btDev, &radioState) == ERROR_NONE && radioState == BT_RADIO_STATE_ON) {
+            lv_obj_add_state(_switchWidget, LV_STATE_CHECKED);
+            handleSwitchToggle(true);
+        }
+    }
 }
 
 void MediaKeys::onHide(AppHandle /*appHandle*/) {
-    if (_hidDevice) bluetooth_hid_device_stop(_hidDevice);
-    if (_btDevice) bluetooth_remove_event_callback(_btDevice, btEventCallback);
-    if (_btDevice && _radioWasOff) bluetooth_set_radio_enabled(_btDevice, false);
-    _btDevice = nullptr;
-    _hidDevice = nullptr;
-    _isEnabled = false;
     _radioEnabling = false;
-    _radioWasOff = false;
-
+    _isEnabled = false;
     if (tt_lvgl_hardware_keyboard_is_available()) exitKeyMode();
+    teardownBt();
     if (_keyHighlightTimer) {
         lv_timer_delete(_keyHighlightTimer);
         _keyHighlightTimer = nullptr;

Apps/MediaKeys/main/Source/MediaKeys.h

@@ -2,6 +2,7 @@
 
 #include <TactilityCpp/App.h>
 #include <lvgl.h>
+#include <tactility/device.h>
 #include <tactility/drivers/bluetooth.h>
 #include <tactility/drivers/bluetooth_hid_device.h>
 #include <tt_app.h>
@@ -23,9 +24,10 @@ class MediaKeys final : public App {
     struct Device* _hidDevice = nullptr;
 
     // State - accessed from both LVGL thread and BT callback thread
-    std::atomic<bool> _isEnabled    {false};
-    std::atomic<bool> _radioEnabling{false}; // true while waiting for radio to come ON
-    std::atomic<bool> _radioWasOff  {false}; // true if MediaKeys turned the radio on (so we turn it off)
+    std::atomic<bool> _isEnabled       {false};
+    std::atomic<bool> _radioEnabling   {false}; // true while waiting for radio to come ON
+    std::atomic<bool> _radioWasOff     {false}; // true if we turned the radio on (restore on exit)
+    std::atomic<bool> _deviceWasStarted{false}; // true if we called device_start (restore on exit)
 
     // Static event callbacks
     static void onSwitchToggled(lv_event_t* e);
@@ -36,6 +38,7 @@ class MediaKeys final : public App {
     static void sendKeyTask(void* param);
 
     // Instance methods called by static callbacks
+    void teardownBt(); // remove callback + stop HID + restore radio/device state
     void handleSwitchToggle(bool enabled);
     void handleButtonPress(uint32_t buttonId);
     void startHid(); // called once radio is confirmed ON

Apps/TamaTac/main/Source/TamaTac.cpp

@@ -57,7 +57,6 @@ void TamaTac::onShow(AppHandle context, lv_obj_t* parent) {
     if (sfxEngine == nullptr) {
         sfxEngine = new SfxEngine();
         sfxEngine->start();
-        sfxEngine->applyVolumePreset(SfxEngine::VolumePreset::Normal);
 
         // Load settings
         bool soundEnabled;

Libraries/SfxEngine/Include/SfxEngine.h

@@ -26,6 +26,7 @@
 
 #include <cstdint>
 #include <tactility/device.h>
+#include <tactility/drivers/audio_stream.h>
 #include "freertos/FreeRTOS.h"
 #include "freertos/task.h"
 #include "freertos/queue.h"
@@ -161,12 +162,6 @@ class SfxEngine {
     // Settings
     void setEnabled(bool enabled) { enabled_ = enabled; }
     bool isEnabled() const { return enabled_; }
-    void setVolume(float vol) { masterVolume_ = (vol < 0) ? 0 : (vol > 1.0f) ? 1.0f : vol; }
-    float getVolume() const { return masterVolume_; }
-
-    // Volume presets (consistent with SoundEngine naming)
-    enum class VolumePreset { Quiet, Normal, Loud };
-    void applyVolumePreset(VolumePreset preset);
 
     // Polyphonic gate (consistent with SoundEngine)
     void setPolyphonicGateEnabled(bool enabled) { polyphonicGateEnabled_ = enabled; }
@@ -277,14 +272,21 @@ class SfxEngine {
     // State
     //--------------------------------------------------------------------------
 
-    Device* i2sDevice_ = nullptr;
+    Device* audioStreamDevice_ = nullptr;
+    AudioStreamHandle audioStreamHandle_ = nullptr;
     TaskHandle_t task_ = nullptr;
     SemaphoreHandle_t stopSemaphore_ = nullptr;  // Signaled when audio task exits
     QueueHandle_t msgQueue_ = nullptr;
 
     volatile bool running_ = false;
     volatile bool enabled_ = true;
-    volatile float masterVolume_ = 0.5f;
+
+    // Cached system output volume (0..1), refreshed periodically from the shared
+    // audio_stream device so the preset acts as a relative multiplier on top of it
+    // rather than an absolute level (a "Quiet" preset should sound quiet relative
+    // to whatever the user has the system volume set to, not in absolute terms).
+    float systemVolumeMix_ = 1.0f;
+    int systemVolumePollCounter_ = 0;
 
     // Polyphonic gate
     volatile bool polyphonicGateEnabled_ = true;

Libraries/SfxEngine/README.md

@@ -35,11 +35,8 @@ if (!engine->start()) {
     ESP_LOGE(TAG, "Failed to start SfxEngine");
     return;
 }
-engine->applyVolumePreset(SfxEngine::VolumePreset::Normal);
-
 engine->play(SfxId::Coin);                // Predefined SFX
 engine->playNote(0, 60, 200);             // Manual: voice 0, C4, 200ms
-engine->setVolume(0.7f);                   // Volume control
 
 engine->stop();
 delete engine;
@@ -87,9 +84,11 @@ idf_component_register(
 - `void stopVoice(voice)` - Stop specific voice
 
 ### Settings
-- `void setVolume(float)` - Master volume (0.0-1.0, exponential curve)
 - `void setEnabled(bool)` - Mute/unmute
-- `void applyVolumePreset(VolumePreset)` - Apply Quiet/Normal/Loud preset (configures volume, gate, normalization)
+
+Loudness is controlled by the system output volume (set via the audio_stream device / Settings UI),
+not by SfxEngine itself -- a fixed app-side gain on top of hardware attenuation gets swamped at low
+system volumes, so there's no separate volume control here.
 
 ### Mixing (consistent with SoundEngine)
 - `void setPolyphonicGateEnabled(bool)` - Soft gate when multiple voices clip (default: on)