diff --git a/.gitmodules b/.gitmodules
index c50a5c7..7fb3998 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -10,6 +10,3 @@
 [submodule "third_party/glfw"]
 	path = third_party/glfw
 	url = https://github.com/glfw/glfw.git
-[submodule "third_party/cppzmq"]
-	path = third_party/cppzmq
-	url = https://github.com/zeromq/cppzmq.git
diff --git a/core/audio/device/audio_device_manager.cpp b/core/audio/device/audio_device_manager.cpp
index eabc074..6c0c067 100644
--- a/core/audio/device/audio_device_manager.cpp
+++ b/core/audio/device/audio_device_manager.cpp
@@ -136,18 +136,15 @@ void audio_device_manager::start_render_thread() {
 
 void audio_device_manager::stop_render_thread() {
     render_thread_should_stop_ = true;
-    if (render_thread_.joinable())
-        render_thread_.join();
+    // if (render_thread_.joinable())
+        // render_thread_.join();
     // wait for render thread to stop
-    while (render_thread_running_) {
-        std::this_thread::sleep_for(std::chrono::milliseconds(1));
-    }
+    std::scoped_lock lock(render_thread_mutex_);
     spdlog::info("port_audio render thread stopped");
 }
 
 void audio_device_manager::render_thread() {
     set_thread_name("audio_render");
-    render_thread_running_ = true;
     g_audio_thread_id = std::this_thread::get_id();
     dummy_track* master = g_mixer.get_master();
 
@@ -162,6 +159,7 @@ void audio_device_manager::render_thread() {
     const float milliseconds = frames / rate * 1000; // 512 / 48000
 
     while (!render_thread_should_stop_) {
+        std::scoped_lock lock(render_thread_mutex_);
         g_audio_thread_hub.process_messages();
         if (render_buffers_[0].remainder() < frames) {
              // std::this_thread::sleep_for(std::chrono::milliseconds(static_cast<uint64_t>(milliseconds)));
@@ -173,5 +171,4 @@ void audio_device_manager::render_thread() {
         g_plugin_host_manager.process(frames);
         g_mixer.process(frames, render_buffers_);
     }
-    render_thread_running_ = false;
 }
diff --git a/core/audio/device/audio_device_manager.h b/core/audio/device/audio_device_manager.h
index f35acad..66c1788 100644
--- a/core/audio/device/audio_device_manager.h
+++ b/core/audio/device/audio_device_manager.h
@@ -33,8 +33,8 @@ protected:
     void render_thread();
     std::thread render_thread_;
     circular_buffer_vector_type render_buffers_;
-    std::atomic_bool render_thread_running_ = false;
     std::atomic_bool render_thread_should_stop_ = false;
+    std::mutex render_thread_mutex_;
 #pragma endregion
 private:
     RtAudio::StreamParameters input_params_ = {};
diff --git a/core/audio/midi_sequencer/midi_sequencer.cpp b/core/audio/midi_sequencer/midi_sequencer.cpp
index 91ab892..c1d5778 100644
--- a/core/audio/midi_sequencer/midi_sequencer.cpp
+++ b/core/audio/midi_sequencer/midi_sequencer.cpp
@@ -11,12 +11,13 @@
 
 IMPL_SINGLETON_INSTANCE(midi_sequencer)
 
+smf::MidiFile midifile;
 
 void midi_sequencer::test() {
-    const char* path = R"(F:\VST\VST64\Serum_x64.dll)";
+    const char* path = R"(F:\VST\VST64\Addictive Keys.dll)";
     // host->try_open_editor();
 
-    smf::MidiFile midifile("E:/Projects/AronaStudio/Arona/resources/1.mid");
+    midifile.read("E:/Projects/AronaStudio/Arona/resources/1.mid");
     if (!midifile.status())
         spdlog::critical("Error reading MIDI file");
     midifile.doTimeAnalysis();
@@ -71,6 +72,7 @@ auto midi_sequencer::toggle_play() -> bool {
 }
 
 auto midi_sequencer::create_clip_instance(clip* clip) -> clip_instance* {
+    check(IS_AUDIO_THREAD());
     auto instance = new clip_instance(clip);
     clip_instances_.push_back(instance);
     return instance;
diff --git a/core/audio/midi_sequencer/midi_sequencer.h b/core/audio/midi_sequencer/midi_sequencer.h
index 9f06355..54ff49b 100644
--- a/core/audio/midi_sequencer/midi_sequencer.h
+++ b/core/audio/midi_sequencer/midi_sequencer.h
@@ -15,7 +15,7 @@ public:
 
     void init(singleton_initliazer& initliazer) override;
     void process(double sample_rate, uint32_t delta_frames);
-    auto toggle_play() -> bool ;
+    auto toggle_play() -> bool;
 
     template<class T>
     auto create_clip() -> T* {
diff --git a/core/audio/misc/audio_buffer_pool.cpp b/core/audio/misc/audio_buffer_pool.cpp
index eb22c0e..0162506 100644
--- a/core/audio/misc/audio_buffer_pool.cpp
+++ b/core/audio/misc/audio_buffer_pool.cpp
@@ -12,6 +12,7 @@ void audio_buffer_pool::release(singleton_release_guard& release_guard) {
     for (auto& pool : pool_map_) {
         delete pool.second;
     }
+    pool_map_.clear();
 }
 
 sample_t* audio_buffer_pool::alloc(uint32_t block_size) {
@@ -22,5 +23,6 @@ sample_t* audio_buffer_pool::alloc(uint32_t block_size) {
 }
 
 void audio_buffer_pool::free(sample_t* block, uint32_t block_size) {
-    pool_map_[block_size]->deallocate(block);
+    if (const auto pool = pool_map_[block_size])
+        pool->deallocate(block);
 }
diff --git a/core/audio/mixer/channel_interface.cpp b/core/audio/mixer/channel_interface.cpp
index dd5fbfd..ace6ae6 100644
--- a/core/audio/mixer/channel_interface.cpp
+++ b/core/audio/mixer/channel_interface.cpp
@@ -134,11 +134,11 @@ void channel_interface::remove_track(mixer_track* track) {
 }
 
 mixer_channel_interface::mixer_channel_interface(mixer_track* track) : channel_interface(0, 2), track_(track) {
-    node_ = new mixer_channel_node(this, track, 0);
+    node_ = get_pool_obj<mixer_channel_node>(this, track, 0);
     set_output_channel(0, node_);
 }
 
 mixer_channel_interface::~mixer_channel_interface() {
-    delete node_;
+    free_pool_obj(node_);
 }
 
diff --git a/core/audio/mixer/mixer.cpp b/core/audio/mixer/mixer.cpp
index 21c9a9b..7ba882b 100644
--- a/core/audio/mixer/mixer.cpp
+++ b/core/audio/mixer/mixer.cpp
@@ -9,6 +9,60 @@
 
 IMPL_SINGLETON_INSTANCE(mixer)
 
+void mixer_thread_cache::add_track(mixer_track* track) {
+    std::lock_guard lock(mutex_);
+    tracks_.push_back(track);
+}
+
+void mixer_thread_cache::remove_track(mixer_track* track) {
+    std::lock_guard lock(mutex_);
+
+    if (const auto it = std::ranges::find(tracks_, track); it != tracks_.end()) {
+        tracks_.erase(it);
+    }
+    processor_.remove_track(track);
+    on_remove_track.broadcast(track);
+
+    g_main_thread_hub.push_message([track, this]() {
+        on_remove_track_main_thread.broadcast(track);
+        track_pool::free(track);
+    });
+}
+
+void mixer_thread_cache::process(uint32_t in_frames, circular_buffer_vector_type& out_buffer) {
+    std::lock_guard lock(mutex_);
+    processor_.process(in_frames);
+    processor_.pop_master(in_frames, out_buffer);
+    ready_ = true;
+}
+
+void mixer_thread_cache::reset() {
+    std::lock_guard lock(mutex_);
+    for (const auto track : tracks_) {
+        track->clear();
+    }
+}
+
+void mixer_thread_cache::add_link(mixer_track* in_source, mixer_track* in_target, float in_gain) {
+    std::lock_guard lock(mutex_);
+    processor_.add_link(in_source, in_target, in_gain);
+}
+
+void mixer_thread_cache::remove_link(mixer_track* in_source, mixer_track* in_target) {
+    std::lock_guard lock(mutex_);
+    processor_.remove_link(in_source, in_target);
+}
+
+void mixer_thread_cache::build_process_node() {
+    std::lock_guard lock(mutex_);
+    processor_.update_all();
+}
+
+void mixer_thread_cache::update_latency() {
+    std::lock_guard lock(mutex_);
+    processor_.update_latency();
+}
+
 void mixer::init(singleton_initliazer& initliazer) {
     singleton_t<mixer>::init(initliazer);
     on_latency_offset_changed.add_raw(this, &mixer::on_mixer_latency_changed);
@@ -17,17 +71,12 @@ void mixer::init(singleton_initliazer& initliazer) {
 
     null_channel_node::init();
 
-    zero_track_ = new dummy_track();
-    zero_track_->rename("zero");
+    zero_track_ = track_pool::construct<zero_track>();
     zero_track_->init();
-
-    master_ = new dummy_track();
-    master_->rename("master");
-    master_->init();
-    push_track(master_);
+    master_ = create_dummy_track("master");
 }
 
-void mixer::begin_release(singleton_release_guard &release_guard) {
+void mixer::begin_release(singleton_release_guard& release_guard) {
     singleton::begin_release(release_guard);
     on_latency_offset_changed.remove_object(this);
 }
@@ -36,90 +85,37 @@ void mixer::release(singleton_release_guard& release_guard) {
     singleton_t<mixer>::release(release_guard);
     release_guard.require_release<audio_device_manager>();
     null_channel_node::destroy();
-    for (auto track : tracks_) {
-        delete track;
-    }
-    delete zero_track_;
-    tracks_.clear();
+    track_pool::free_all();
 }
 
-dummy_track* mixer::create_dummy_track(const std::string& in_name) {
-    ready_dirty();
-    auto* track = new dummy_track();
+dummy_track* mixer::create_dummy_track(const std::string& in_name, bool register_to_manager) {
+    auto* track = track_pool::construct<dummy_track>();
     track->init();
     track->rename(in_name);
 
-    g_audio_thread_hub.push_message([track, this]() {
-        processor_.add_link(track, get_master(), 1.0f);
-        thread_register_track(track);
-    });
+    if (register_to_manager) {
+        mixer_thread_cache_.add_track(track);
+        mixer_thread_cache_.add_link(track, get_master(), 1.0f);
+    }
     return track;
 }
 
-instrument_track* mixer::create_instrument_track(plugin_host* in_instrument) {
-    ready_dirty();
-    auto* track = new instrument_track(in_instrument);
+instrument_track* mixer::create_instrument_track(plugin_host* in_instrument, bool register_to_manager) {
+    auto* track = track_pool::construct<instrument_track>(in_instrument);
     track->init();
 
-    // register track
-    g_audio_thread_hub.push_message([track, this] {
-        processor_.add_link(track, get_master(), 1.0f);
-        thread_register_track(track);
-    });
+    if (register_to_manager) {
+        mixer_thread_cache_.add_track(track);
+        mixer_thread_cache_.add_link(track, get_master(), 1.0f);
+    }
     return track;
 }
 
 void mixer::remove_track(mixer_track* track) {
-    g_audio_thread_hub.push_message([track, this] {
-        if (const auto it = std::ranges::find(tracks_, track); it != tracks_.end()) {
-            tracks_.erase(it);
-        }
-        processor_.remove_track(track);
-        on_remove_track.broadcast(track);
-
-        g_main_thread_hub.push_message([track, this]() {
-            on_remove_track_main_thread.broadcast(track);
-            if (track == selected_track)
-                selected_track = nullptr;
-            delete track;
-        });
-    });
-}
-
-void mixer::process(uint32_t in_frames, circular_buffer_vector_type& out_buffer) {
-    processor_.process(in_frames);
-    processor_.pop_master(in_frames, out_buffer);
-    ready_ = true;
-}
-
-void mixer::reset() {
-    for (const auto track : tracks_) {
-        track->clear();
-    }
-}
-
-void mixer::request_build_process_node() {
-    g_audio_thread_hub.push_message([this] {
-        processor_.update_all();
-    });
-}
-
-void mixer::push_track(mixer_track* track) {
-    tracks_.push_back(track);
-}
-
-void mixer::thread_register_track(mixer_track* track) {
-    push_track(track);
-    processor_.update_all();
-    on_add_track.broadcast(track);
-    g_main_thread_hub.push_message([track, this] {
-        on_add_track_main_thread.broadcast(track);
-    });
+    mixer_thread_cache_.remove_track(track);
+    if (track == selected_track) selected_track = nullptr;
 }
 
 void mixer::on_mixer_latency_changed() {
-    ready_dirty();
-    g_audio_thread_hub.push_message([this] {
-        processor_.update_latency();
-    });
+    mixer_thread_cache_.update_latency();
 }
diff --git a/core/audio/mixer/mixer.h b/core/audio/mixer/mixer.h
index b4c2a53..9ce39a5 100644
--- a/core/audio/mixer/mixer.h
+++ b/core/audio/mixer/mixer.h
@@ -14,6 +14,41 @@ class plugin_host;
 class channel_interface;
 class mixer_track;
 
+using track_pool = inherit_obj_pool<mixer_track, zero_track, dummy_track, instrument_track>;
+inline multicast_delegate<mixer_track*> on_add_track;
+inline multicast_delegate<mixer_track*> on_add_track_main_thread;
+inline multicast_delegate<mixer_track*> on_remove_track;
+inline multicast_delegate<mixer_track*> on_remove_track_main_thread;
+
+class mixer_thread_cache {
+public:
+    void add_track(mixer_track* track);
+    void remove_track(mixer_track* track);
+    void process(uint32_t in_frames, circular_buffer_vector_type& out_buffer);
+    void reset();
+
+    void add_link(mixer_track* in_source, mixer_track* in_target, float in_gain);
+    void remove_link(mixer_track* in_source, mixer_track* in_target);
+
+    void build_process_node();
+    void update_latency();
+
+    auto get_tracks() -> const std::vector<mixer_track*>& {
+        return tracks_;
+    }
+    auto begin() {
+        return tracks_.begin();
+    }
+    auto end() {
+        return tracks_.end();
+    }
+private:
+    std::vector<mixer_track*> tracks_;
+    mixer_processor processor_;
+    std::atomic<bool> ready_ = false;
+    std::mutex mutex_;
+};
+
 class mixer : public singleton_t<mixer> {
     typedef std::pair<int32_t, std::vector<mixer_track*>> layer_type;
 public:
@@ -22,38 +57,32 @@ public:
     void release(singleton_release_guard& release_guard) override;
     const char* get_name() override { return "mixer"; }
 
-    dummy_track* create_dummy_track(const std::string& in_name);
-    instrument_track* create_instrument_track(plugin_host* in_instrument);
+    dummy_track* create_dummy_track(const std::string& in_name, bool register_to_manager = true);
+    instrument_track* create_instrument_track(plugin_host* in_instrument, bool register_to_manager = true);
     void remove_track(mixer_track* track);
-    [[nodiscard]] const std::vector<mixer_track*>& get_tracks() const { return tracks_; }
 
-    void process(uint32_t in_frames, circular_buffer_vector_type& out_buffer);
-    void reset();
+    void process(uint32_t in_frames, circular_buffer_vector_type& out_buffer) {
+        if (need_build_process_node_) {
+            mixer_thread_cache_.build_process_node();
+            need_build_process_node_ = false;
+        }
+        mixer_thread_cache_.process(in_frames, out_buffer);
+    }
+    void reset() { mixer_thread_cache_.reset(); }
+    void request_build_process_node() { need_build_process_node_ = true; }
+    auto get_tracks() -> const std::vector<mixer_track*>& { return mixer_thread_cache_.get_tracks(); }
 
     [[nodiscard]] auto get_master() const -> dummy_track* { return master_; }
-    [[nodiscard]] auto get_zero_track() const -> dummy_track* { return zero_track_; }
-    void request_build_process_node();
-    bool is_ready() const { return ready_; }
-    void ready_dirty() { ready_ = false; }
-
-    multicast_delegate<mixer_track*> on_add_track;
-    multicast_delegate<mixer_track*> on_add_track_main_thread;
-    multicast_delegate<mixer_track*> on_remove_track;
-    multicast_delegate<mixer_track*> on_remove_track_main_thread;
+    [[nodiscard]] auto get_zero_track() const -> zero_track* { return zero_track_; }
 
     mixer_track* selected_track = nullptr;
 private:
-    void push_track(mixer_track* track);
-
-    void thread_register_track(mixer_track* track);
-
     void on_mixer_latency_changed();
 
-    dummy_track* master_;
-    dummy_track* zero_track_; // 用于没有任何音频输出的通道
-    std::vector<mixer_track*> tracks_;
-    mixer_processor processor_;
-    std::atomic<bool> ready_ = false;
+    dummy_track* master_ = nullptr;
+    zero_track* zero_track_ = nullptr; // 用于没有任何音频输出的通道
+    std::atomic<bool> need_build_process_node_ = false;
+    mixer_thread_cache mixer_thread_cache_;
 };
 
 DEFINE_SINGLETON_INSTANCE(mixer)
diff --git a/core/audio/mixer/mixer_track.cpp b/core/audio/mixer/mixer_track.cpp
index 0ce7fef..3442317 100644
--- a/core/audio/mixer/mixer_track.cpp
+++ b/core/audio/mixer/mixer_track.cpp
@@ -7,8 +7,7 @@
 #include "thread_message/thread_message_hubs.h"
 
 mixer_track::~mixer_track() {
-    delete channel_interface_;
-    channel_interface_ = nullptr;
+    free_pool_obj(channel_interface_);
     for (auto e : effects_) {
         // e->on_latency_changed.remove_all(this);
         get_plugin_host_manager()->remove_effect_plugin_host(e);
@@ -25,7 +24,7 @@ void mixer_track::init() {
         buffer.set_capacity(block_size * 2);
     }
 
-    channel_interface_ = new mixer_channel_interface(this);
+    channel_interface_ = get_pool_obj<mixer_channel_interface>(this);
 }
 
 void mixer_track::add_effect(plugin_host* in_effect) {
@@ -67,7 +66,7 @@ void mixer_track::push_ui_buffer(const audio_buffer& in_buffer) {
     }
 }
 
-instrument_track::instrument_track(plugin_host* in_instrument): mixer_track(mixer_track_type::instrument)
+instrument_track::instrument_track(plugin_host* in_instrument): mixer_track(type)
                                                             , instrument_(in_instrument) {}
 
 void instrument_track::rename(const std::string& in_name) {
diff --git a/core/audio/mixer/mixer_track.h b/core/audio/mixer/mixer_track.h
index f86c44e..780a3fc 100644
--- a/core/audio/mixer/mixer_track.h
+++ b/core/audio/mixer/mixer_track.h
@@ -3,17 +3,16 @@
 #include <utility>
 
 #include "latency_compensator.h"
-#include "../../misc/mempool.h"
 #include "audio/misc/audio_buffer.h"
 #include "audio/misc/circular_audio_buffer.h"
-#include "misc/delegates.h"
 
-class channel_interface;
+class mixer_channel_interface;
 class mixer_track;
 class plugin_host;
 
 enum class mixer_track_type {
     unknown,
+    zero,
     dummy,
     instrument,
 };
@@ -48,7 +47,7 @@ public:
 
     [[nodiscard]] auto get_type() const -> mixer_track_type { return type_; }
 
-    [[nodiscard]] auto get_channel_interface() const -> channel_interface* { return channel_interface_; }
+    [[nodiscard]] auto get_channel_interface() const -> mixer_channel_interface* { return channel_interface_; }
 
     void set_volume(float in_volume) { volume_ = in_volume; }
     [[nodiscard]] auto get_volume() const -> float { return volume_; }
@@ -69,12 +68,12 @@ private:
     circular_buffer_vector_type ui_buffers_;
     std::vector<plugin_host*> effects_{};
     audio_buffer buffer_;
-    channel_interface* channel_interface_ = nullptr;
+    mixer_channel_interface* channel_interface_ = nullptr;
     const uint64_t id_ = 0;
     float volume_ = 1.0f;
 };
 
-class instrument_track : public mixer_track, public pool_obj<instrument_track> {
+class instrument_track : public mixer_track {
 public:
     static constexpr auto type = mixer_track_type::instrument;
 
@@ -92,10 +91,10 @@ private:
     plugin_host* instrument_;
 };
 
-class dummy_track : public mixer_track, public pool_obj<dummy_track> {
+class dummy_track : public mixer_track {
 public:
     static constexpr auto type = mixer_track_type::dummy;
-    dummy_track() : mixer_track(mixer_track_type::dummy) {}
+    dummy_track() : mixer_track(type) {}
 
     void rename(const std::string& in_name) override { name_ = in_name; }
     [[nodiscard]] auto get_name() const -> std::string override { return name_; }
@@ -103,3 +102,14 @@ public:
 private:
     std::string name_;
 };
+
+class zero_track : public mixer_track {
+public:
+    static constexpr auto type = mixer_track_type::zero;
+    zero_track() : mixer_track(type) {}
+
+    [[nodiscard]] auto get_name() const -> std::string override { return "zero"; }
+    void rename(const std::string& in_name) override {}
+private:
+
+};
diff --git a/core/audio/plugin_host/plugin_host.cpp b/core/audio/plugin_host/plugin_host.cpp
index 9259955..e27b7f2 100644
--- a/core/audio/plugin_host/plugin_host.cpp
+++ b/core/audio/plugin_host/plugin_host.cpp
@@ -24,9 +24,11 @@ void plugin_host::on_update_buffer_size(int buffer_size)
     }
 }
 
-void plugin_host::push_stop_all_notes(uint32_t frame_delta) {
-    smf::MidiEvent event(0xB0, 0x7B, 0x00);
-    push_midi(event, frame_delta);
+void plugin_host::push_stop_all_notes(uint8_t channel) {
+    for (uint8_t i = 0; i < 127; ++i) {
+        smf::MidiEvent event(0x80 | channel, i, 0x00);
+        push_midi(event, 0);
+    }
 }
 
 void plugin_host::try_open_editor() {
diff --git a/core/audio/plugin_host/plugin_host.h b/core/audio/plugin_host/plugin_host.h
index 6aff088..21262e2 100644
--- a/core/audio/plugin_host/plugin_host.h
+++ b/core/audio/plugin_host/plugin_host.h
@@ -59,7 +59,7 @@ public:
 
     virtual void process(uint32_t frame_num) = 0;
     virtual void push_midi(const smf::MidiEvent& event, uint32_t frame_delta) = 0;
-    void push_stop_all_notes(uint32_t frame_delta = 0);
+    void push_stop_all_notes(uint8_t channel = 0);
 
     void try_open_editor();
 
diff --git a/core/audio/plugin_host/plugin_host_manager.cpp b/core/audio/plugin_host/plugin_host_manager.cpp
index 686b801..92e0b90 100644
--- a/core/audio/plugin_host/plugin_host_manager.cpp
+++ b/core/audio/plugin_host/plugin_host_manager.cpp
@@ -16,8 +16,7 @@ IMPL_SINGLETON_INSTANCE(plugin_host_manager)
 
 void plugin_host_manager::init(singleton_initliazer& initliazer) {
     singleton_t::init(initliazer);
-    auto* mixer_ptr = initliazer.require<mixer>();
-    mixer_ptr->on_remove_track.add_raw(this, &plugin_host_manager::on_mixer_track_removed);
+    on_remove_track.add_raw(this, &plugin_host_manager::on_mixer_track_removed);
 }
 
 void plugin_host_manager::release(singleton_release_guard& release_guard) {
@@ -77,7 +76,7 @@ void plugin_host_manager::remove_instrument_plugin_host(plugin_host* host) {
 plugin_host* plugin_host_manager::load_plugin(const char* path) {
     auto host = new vst2_plugin_host();
     try {
-        host->load_plugin(path);
+        host->load(path);
     } catch (std::exception& e) {
         spdlog::error("Failed to load plugin: {}", e.what());
         delete host;
@@ -91,14 +90,15 @@ plugin_host* plugin_host_manager::load_plugin(const char* path) {
 }
 
 void plugin_host_manager::register_instrument_plugin(plugin_host* host) {
-    instrument_plugins_.push_back(host);
     g_audio_thread_hub.push_message([this, host]() {
+        instrument_plugins_.push_back(host);
         instrument_track* instrument_track = g_mixer.create_instrument_track(host);
         host->channel->set_input_channel(instrument_track->get_channel_interface()->input_channel_nodes);
         host->channel->set_output_channel(instrument_track->get_channel_interface()->output_channel_nodes);
         host->owner_tracks.push_back(instrument_track);
         host->update_channel_node_name();
         update_taskflow(g_audio_device_manager.get_buffer_size());
+
         g_main_thread_hub.push_message([host, this]() {
             on_instrument_added.broadcast(host);
         });
@@ -106,16 +106,19 @@ void plugin_host_manager::register_instrument_plugin(plugin_host* host) {
 }
 
 void plugin_host_manager::process(uint32_t in_frames) {
+    check(IS_AUDIO_THREAD());
     g_executor->run(taskflow_).wait();
 }
 
 void plugin_host_manager::on_mixer_track_removed(mixer_track* track) {
+    check(IS_AUDIO_THREAD());
     for (auto host : plugin_hosts_) {
         host->channel->remove_track(track);
     }
 }
 
 void plugin_host_manager::update_taskflow(uint32_t in_frames) {
+    check(IS_AUDIO_THREAD());
     tf::Taskflow taskflow;
     for (auto host : instrument_plugins_) {
         taskflow.emplace([host, in_frames] {
diff --git a/core/audio/plugin_host/plugin_host_manager.h b/core/audio/plugin_host/plugin_host_manager.h
index b81facd..0f4b92f 100644
--- a/core/audio/plugin_host/plugin_host_manager.h
+++ b/core/audio/plugin_host/plugin_host_manager.h
@@ -1,9 +1,10 @@
 #pragma once
+#include <coroutine>
+
 #include "misc/delegates.h"
 #include "misc/singleton/singleton.h"
 #include "taskflow/taskflow.hpp"
 #include "plugin_host.h"
-#include "../../misc/mempool.h"
 #include <unordered_map>
 
 class mixer_track;
diff --git a/third_party/cppzmq b/third_party/cppzmq
deleted file mode 160000
index 6164cf7..0000000
--- a/third_party/cppzmq
+++ /dev/null
@@ -1 +0,0 @@
-Subproject commit 6164cf7dbc1df6d1bd8e4c6c5f8e52d7dea63aa7