diff --git a/source/backend/plugin/CarlaPluginJack.cpp b/source/backend/plugin/CarlaPluginJack.cpp
index 58b5fd6a4..2d4039c52 100644
--- a/source/backend/plugin/CarlaPluginJack.cpp
+++ b/source/backend/plugin/CarlaPluginJack.cpp
@@ -121,11 +121,13 @@ protected:
 
             CarlaString ldpreload;
 
+            /*
             if (options.frontendWinId != 0)
             {
                 ldpreload = (CarlaString(options.binaryDir)
                           + "/libcarla_interposer-x11.so");
             }
+            */
 
             const ScopedEngineEnvironmentLocker _seel(kEngine);
 
diff --git a/source/libjack/libjack.cpp b/source/libjack/libjack.cpp
index a33cd0542..677c5d298 100644
--- a/source/libjack/libjack.cpp
+++ b/source/libjack/libjack.cpp
@@ -18,12 +18,8 @@
 #include "libjack.hpp"
 #include <sys/prctl.h>
 
-using juce::File;
 using juce::FloatVectorOperations;
-using juce::MemoryBlock;
-using juce::String;
 using juce::Time;
-using juce::Thread;
 
 CARLA_BACKEND_START_NAMESPACE
 
@@ -37,7 +33,7 @@ public:
 
     CarlaJackAppClient()
         : Thread("CarlaJackAppClient"),
-          fServer(),
+          fServer(this),
           fAudioPoolCopy(nullptr),
           fIsValid(false),
           fIsOffline(false),
@@ -293,6 +289,18 @@ void CarlaJackAppClient::handleNonRtData()
             signalThreadShouldExit();
             break;
         }
+
+        if (opcode != kPluginBridgeNonRtClientPing)
+        {
+            static int shownNull = 0;
+            if (opcode == kPluginBridgeNonRtClientNull)
+            {
+                if (shownNull > 5)
+                    continue;
+                ++shownNull;
+            }
+            carla_stdout("CarlaJackAppClient::handleNonRtData() - opcode %s handled", PluginBridgeNonRtClientOpcode2str(opcode));
+        }
     }
 }
 
@@ -595,6 +603,13 @@ void CarlaJackAppClient::run()
                 signalThreadShouldExit();
                 break;
             }
+
+//#ifdef DEBUG
+            if (opcode != kPluginBridgeRtClientProcess && opcode != kPluginBridgeRtClientMidiEvent)
+            {
+                carla_stdout("CarlaJackAppClientRtThread::run() - opcode %s done", PluginBridgeRtClientOpcode2str(opcode));
+            }
+//#endif
         }
     }
 
@@ -668,6 +683,8 @@ static CarlaJackAppClient gClient;
 CARLA_EXPORT
 jack_client_t* jack_client_open(const char* client_name, jack_options_t options, jack_status_t* status, ...)
 {
+    carla_stdout("%s(%s, 0x%x, %p)", __FUNCTION__, client_name, options, status);
+
     if (JackClientState* const client = gClient.addClient(client_name))
         return (jack_client_t*)client;
 
@@ -686,6 +703,8 @@ jack_client_t* jack_client_new(const char* client_name)
 CARLA_EXPORT
 int jack_client_close(jack_client_t* client)
 {
+    carla_stdout("%s(%p)", __FUNCTION__, client);
+
     JackClientState* const jclient = (JackClientState*)client;
     CARLA_SAFE_ASSERT_RETURN(jclient != nullptr, 1);
 
@@ -696,11 +715,13 @@ int jack_client_close(jack_client_t* client)
 CARLA_EXPORT
 pthread_t jack_client_thread_id(jack_client_t* client)
 {
+    carla_stdout("%s(%p)", __FUNCTION__, client);
+
     JackClientState* const jclient = (JackClientState*)client;
     CARLA_SAFE_ASSERT_RETURN(jclient != nullptr, 0);
 
     CarlaJackAppClient* const jackAppPtr = jclient->server.jackAppPtr;
-    CARLA_SAFE_ASSERT_RETURN(jackAppPtr != nullptr, 0);
+    CARLA_SAFE_ASSERT_RETURN(jackAppPtr != nullptr && jackAppPtr == &gClient, 0);
 
     return (pthread_t)jackAppPtr->getThreadId();
 }
@@ -718,11 +739,21 @@ CARLA_BACKEND_END_NAMESPACE
 CARLA_BACKEND_USE_NAMESPACE
 
 CARLA_EXPORT
-int jack_client_real_time_priority(jack_client_t*)
+int jack_client_real_time_priority(jack_client_t* client)
 {
-    carla_stdout("CarlaJackAppClient :: %s", __FUNCTION__);
+    carla_stdout("%s(%p)", __FUNCTION__, client);
 
     return -1;
 }
 
+typedef void (*JackSessionCallback)(jack_session_event_t*, void*);
+
+CARLA_EXPORT
+int jack_set_session_callback(jack_client_t* client, JackSessionCallback callback, void* arg)
+{
+    carla_stdout("%s(%p, %p, %p)", __FUNCTION__, client, callback, arg);
+
+    return 0;
+}
+
 // --------------------------------------------------------------------------------------------------------------------
diff --git a/source/libjack/libjack.hpp b/source/libjack/libjack.hpp
index f20007426..07033279e 100644
--- a/source/libjack/libjack.hpp
+++ b/source/libjack/libjack.hpp
@@ -65,6 +65,7 @@ struct JackPortState {
     void* buffer;
     uint index;
     uint flags;
+    bool isMidi;
     bool isSystem;
 
     JackPortState()
@@ -73,14 +74,16 @@ struct JackPortState {
           buffer(nullptr),
           index(0),
           flags(0),
+          isMidi(false),
           isSystem(false) {}
 
-    JackPortState(const char* const cn, const char* const pn, const uint i, const uint f, const bool sys)
+    JackPortState(const char* const cn, const char* const pn, const uint i, const uint f, const bool midi, const bool sys)
         : name(strdup(pn)),
           fullname(nullptr),
           buffer(nullptr),
           index(i),
           flags(f),
+          isMidi(midi),
           isSystem(sys)
     {
         char strBuf[STR_MAX+1];
@@ -108,8 +111,8 @@ struct JackClientState {
 
     LinkedList<JackPortState*> audioIns;
     LinkedList<JackPortState*> audioOuts;
-    LinkedList<JackPortState> midiIns;
-    LinkedList<JackPortState> midiOuts;
+    LinkedList<JackPortState*> midiIns;
+    LinkedList<JackPortState*> midiOuts;
 
     JackShutdownCallback shutdownCb;
     void* shutdownCbPtr;
@@ -172,6 +175,18 @@ struct JackClientState {
                 delete jport;
         }
 
+        for (LinkedList<JackPortState*>::Itenerator it = midiIns.begin2(); it.valid(); it.next())
+        {
+            if (JackPortState* const jport = it.getValue(nullptr))
+                delete jport;
+        }
+
+        for (LinkedList<JackPortState*>::Itenerator it = midiOuts.begin2(); it.valid(); it.next())
+        {
+            if (JackPortState* const jport = it.getValue(nullptr))
+                delete jport;
+        }
+
         free(name);
         name = nullptr;
 
@@ -189,8 +204,8 @@ struct JackServerState {
     bool playing;
     jack_position_t position;
 
-    JackServerState()
-        : jackAppPtr(nullptr),
+    JackServerState(CarlaJackAppClient* const app)
+        : jackAppPtr(app),
           bufferSize(0),
           sampleRate(0.0),
           playing(false)
diff --git a/source/libjack/libjack_base.cpp b/source/libjack/libjack_base.cpp
index 4bbf5b03c..f5c2c5c57 100644
--- a/source/libjack/libjack_base.cpp
+++ b/source/libjack/libjack_base.cpp
@@ -40,8 +40,10 @@ const char* jack_get_version_string(void)
 // --------------------------------------------------------------------------------------------------------------------
 
 CARLA_EXPORT
-int jack_is_realtime(jack_client_t*)
+int jack_is_realtime(jack_client_t* client)
 {
+    carla_stdout("%s(%p)", __FUNCTION__, client);
+
     return 1;
 }
 
@@ -50,6 +52,8 @@ int jack_is_realtime(jack_client_t*)
 CARLA_EXPORT
 void jack_free(void* ptr)
 {
+    carla_stdout("%s(%p)", __FUNCTION__, ptr);
+
     free(ptr);
 }
 
diff --git a/source/libjack/libjack_callbacks.cpp b/source/libjack/libjack_callbacks.cpp
index 85fc20d0e..b2c2d47a4 100644
--- a/source/libjack/libjack_callbacks.cpp
+++ b/source/libjack/libjack_callbacks.cpp
@@ -22,14 +22,18 @@ CARLA_BACKEND_USE_NAMESPACE
 // --------------------------------------------------------------------------------------------------------------------
 
 CARLA_EXPORT
-int jack_set_thread_init_callback(jack_client_t*, JackThreadInitCallback, void*)
+int jack_set_thread_init_callback(jack_client_t* client, JackThreadInitCallback callback, void* arg)
 {
+    carla_stdout("%s(%p, %p, %p)", __FUNCTION__, client, callback, arg);
+
     return 0;
 }
 
 CARLA_EXPORT
 void jack_on_shutdown(jack_client_t* client, JackShutdownCallback callback, void* arg)
 {
+    carla_stdout("%s(%p, %p, %p)", __FUNCTION__, client, callback, arg);
+
     JackClientState* const jclient = (JackClientState*)client;
     CARLA_SAFE_ASSERT_RETURN(jclient != nullptr,);
 
@@ -42,6 +46,8 @@ void jack_on_shutdown(jack_client_t* client, JackShutdownCallback callback, void
 CARLA_EXPORT
 void jack_on_info_shutdown(jack_client_t* client, JackInfoShutdownCallback callback, void* arg)
 {
+    carla_stdout("%s(%p, %p, %p)", __FUNCTION__, client, callback, arg);
+
     JackClientState* const jclient = (JackClientState*)client;
     CARLA_SAFE_ASSERT_RETURN(jclient != nullptr,);
 
@@ -54,6 +60,8 @@ void jack_on_info_shutdown(jack_client_t* client, JackInfoShutdownCallback callb
 CARLA_EXPORT
 int jack_set_process_callback(jack_client_t* client, JackProcessCallback callback, void* arg)
 {
+    carla_stdout("%s(%p, %p, %p)", __FUNCTION__, client, callback, arg);
+
     JackClientState* const jclient = (JackClientState*)client;
     CARLA_SAFE_ASSERT_RETURN(jclient != nullptr, 1);
 
@@ -67,6 +75,8 @@ int jack_set_process_callback(jack_client_t* client, JackProcessCallback callbac
 CARLA_EXPORT
 int jack_set_freewheel_callback(jack_client_t* client, JackFreewheelCallback callback, void* arg)
 {
+    carla_stdout("%s(%p, %p, %p)", __FUNCTION__, client, callback, arg);
+
     JackClientState* const jclient = (JackClientState*)client;
     CARLA_SAFE_ASSERT_RETURN(jclient != nullptr, 1);
 
@@ -80,6 +90,8 @@ int jack_set_freewheel_callback(jack_client_t* client, JackFreewheelCallback cal
 CARLA_EXPORT
 int jack_set_buffer_size_callback(jack_client_t* client, JackBufferSizeCallback callback, void* arg)
 {
+    carla_stdout("%s(%p, %p, %p)", __FUNCTION__, client, callback, arg);
+
     JackClientState* const jclient = (JackClientState*)client;
     CARLA_SAFE_ASSERT_RETURN(jclient != nullptr, 1);
 
@@ -93,6 +105,8 @@ int jack_set_buffer_size_callback(jack_client_t* client, JackBufferSizeCallback
 CARLA_EXPORT
 int jack_set_sample_rate_callback(jack_client_t* client, JackSampleRateCallback callback, void* arg)
 {
+    carla_stdout("%s(%p, %p, %p)", __FUNCTION__, client, callback, arg);
+
     JackClientState* const jclient = (JackClientState*)client;
     CARLA_SAFE_ASSERT_RETURN(jclient != nullptr, 1);
 
@@ -104,38 +118,50 @@ int jack_set_sample_rate_callback(jack_client_t* client, JackSampleRateCallback
 }
 
 CARLA_EXPORT
-int jack_set_client_registration_callback(jack_client_t*, JackClientRegistrationCallback, void*)
+int jack_set_client_registration_callback(jack_client_t* client, JackClientRegistrationCallback callback, void* arg)
 {
+    carla_stdout("%s(%p, %p, %p)", __FUNCTION__, client, callback, arg);
+
     return 0;
 }
 
 CARLA_EXPORT
-int jack_set_port_registration_callback(jack_client_t*, JackPortRegistrationCallback, void*)
+int jack_set_port_registration_callback(jack_client_t* client, JackPortRegistrationCallback callback, void* arg)
 {
+    carla_stdout("%s(%p, %p, %p)", __FUNCTION__, client, callback, arg);
+
     return 0;
 }
 
 CARLA_EXPORT
-int jack_set_port_connect_callback(jack_client_t*, JackPortConnectCallback, void*)
+int jack_set_port_connect_callback(jack_client_t* client, JackPortConnectCallback callback, void* arg)
 {
+    carla_stdout("%s(%p, %p, %p)", __FUNCTION__, client, callback, arg);
+
     return 0;
 }
 
 CARLA_EXPORT
-int jack_set_port_rename_callback(jack_client_t*, JackPortRenameCallback, void*)
+int jack_set_port_rename_callback(jack_client_t* client, JackPortRenameCallback callback, void* arg)
 {
+    carla_stdout("%s(%p, %p, %p)", __FUNCTION__, client, callback, arg);
+
     return 0;
 }
 
 CARLA_EXPORT
-int jack_set_graph_order_callback(jack_client_t*, JackGraphOrderCallback, void*)
+int jack_set_graph_order_callback(jack_client_t* client, JackGraphOrderCallback callback, void* arg)
 {
+    carla_stdout("%s(%p, %p, %p)", __FUNCTION__, client, callback, arg);
+
     return 0;
 }
 
 CARLA_EXPORT
-int jack_set_xrun_callback(jack_client_t*, JackXRunCallback, void*)
+int jack_set_xrun_callback(jack_client_t* client, JackXRunCallback callback, void* arg)
 {
+    carla_stdout("%s(%p, %p, %p)", __FUNCTION__, client, callback, arg);
+
     return 0;
 }
 
diff --git a/source/libjack/libjack_client.cpp b/source/libjack/libjack_client.cpp
index 366602003..3c61a7940 100644
--- a/source/libjack/libjack_client.cpp
+++ b/source/libjack/libjack_client.cpp
@@ -30,6 +30,8 @@ int jack_client_name_size(void)
 CARLA_EXPORT
 char* jack_get_client_name(jack_client_t* client)
 {
+    carla_stdout("%s(%p)", __FUNCTION__, client);
+
     JackClientState* const jclient = (JackClientState*)client;
     CARLA_SAFE_ASSERT_RETURN(jclient != nullptr, nullptr);
 
@@ -66,6 +68,8 @@ void jack_internal_client_close(const char*)
 CARLA_EXPORT
 int jack_activate(jack_client_t* client)
 {
+    carla_stdout("%s(%p)", __FUNCTION__, client);
+
     JackClientState* const jclient = (JackClientState*)client;
     CARLA_SAFE_ASSERT_RETURN(jclient != nullptr, 1);
 
@@ -79,6 +83,8 @@ int jack_activate(jack_client_t* client)
 CARLA_EXPORT
 int jack_deactivate(jack_client_t* client)
 {
+    carla_stdout("%s(%p)", __FUNCTION__, client);
+
     JackClientState* const jclient = (JackClientState*)client;
     CARLA_SAFE_ASSERT_RETURN(jclient != nullptr, 1);
 
diff --git a/source/libjack/libjack_error.cpp b/source/libjack/libjack_error.cpp
index a3e8eef1a..5e43a3916 100644
--- a/source/libjack/libjack_error.cpp
+++ b/source/libjack/libjack_error.cpp
@@ -27,9 +27,7 @@ CARLA_BACKEND_USE_NAMESPACE
 CARLA_EXPORT
 void jack_set_error_function(void (*func)(const char *))
 {
-    carla_stdout("CarlaJackClient :: %s", __FUNCTION__);
-
-    (void)func;
+    carla_stdout("%s(%p)", __FUNCTION__, func);
 }
 
 //extern void (*jack_info_callback)(const char *msg) JACK_OPTIONAL_WEAK_EXPORT;
@@ -37,9 +35,7 @@ void jack_set_error_function(void (*func)(const char *))
 CARLA_EXPORT
 void jack_set_info_function(void (*func)(const char *))
 {
-    carla_stdout("CarlaJackClient :: %s", __FUNCTION__);
-
-    (void)func;
+    carla_stdout("%s(%p)", __FUNCTION__, func);
 }
 
 // --------------------------------------------------------------------------------------------------------------------
diff --git a/source/libjack/libjack_midi.cpp b/source/libjack/libjack_midi.cpp
index bf51872ac..b79a7cd6d 100644
--- a/source/libjack/libjack_midi.cpp
+++ b/source/libjack/libjack_midi.cpp
@@ -25,39 +25,47 @@ CARLA_BACKEND_USE_NAMESPACE
 CARLA_EXPORT
 jack_nframes_t jack_midi_get_event_count(void*)
 {
-    carla_stdout("CarlaJackClient :: %s", __FUNCTION__);
-
     return 0;
 }
 
 CARLA_EXPORT
 int jack_midi_event_get(jack_midi_event_t*, void*, uint32_t)
 {
-    carla_stdout("CarlaJackClient :: %s", __FUNCTION__);
-
     return ENODATA;
 }
 
-// void
-// jack_midi_clear_buffer(void *port_buffer) JACK_OPTIONAL_WEAK_EXPORT;
+CARLA_EXPORT
+void jack_midi_clear_buffer(void*)
+{
+}
 
-// void
-// jack_midi_reset_buffer(void *port_buffer) JACK_OPTIONAL_WEAK_EXPORT;
+CARLA_EXPORT
+void jack_midi_reset_buffer(void*)
+{
+}
 
-// size_t
-// jack_midi_max_event_size(void* port_buffer) JACK_OPTIONAL_WEAK_EXPORT;
+CARLA_EXPORT
+size_t jack_midi_max_event_size(void*)
+{
+    return 0;
+}
 
-// jack_midi_data_t*
-// jack_midi_event_reserve(void *port_buffer,
-//                         jack_nframes_t  time,
-//                         size_t data_size) JACK_OPTIONAL_WEAK_EXPORT;
+CARLA_EXPORT
+jack_midi_data_t* jack_midi_event_reserve(void*, jack_nframes_t, size_t)
+{
+    return nullptr;
+}
 
-// int
-// jack_midi_event_write(void *port_buffer,
-//                       jack_nframes_t time,
-//                       const jack_midi_data_t *data,
-//                       size_t data_size) JACK_OPTIONAL_WEAK_EXPORT;
+CARLA_EXPORT
+int jack_midi_event_write(void*, jack_nframes_t, const jack_midi_data_t*, size_t)
+{
+    return ENOBUFS;
+}
 
-// uint32_t jack_midi_get_lost_event_count(void *port_buffer) JACK_OPTIONAL_WEAK_EXPORT;
+CARLA_EXPORT
+uint32_t jack_midi_get_lost_event_count(void*)
+{
+    return 0;
+}
 
 // --------------------------------------------------------------------------------------------------------------------
diff --git a/source/libjack/libjack_port-searching.cpp b/source/libjack/libjack_port-searching.cpp
index 65d80158d..bfed11182 100644
--- a/source/libjack/libjack_port-searching.cpp
+++ b/source/libjack/libjack_port-searching.cpp
@@ -23,9 +23,12 @@ CARLA_BACKEND_USE_NAMESPACE
 // --------------------------------------------------------------------------------------------------------------------
 
 CARLA_EXPORT
-const char** jack_get_ports(jack_client_t*, const char* a, const char* b, unsigned long flags)
+const char** jack_get_ports(jack_client_t* client, const char* a, const char* b, unsigned long flags)
 {
-    carla_stdout("CarlaJackClient :: %s | %s %s %li", __FUNCTION__, a, b, flags);
+    carla_stdout("%s(%p, %s, %s, 0x%lx)", __FUNCTION__, client, a, b, flags);
+
+    JackClientState* const jclient = (JackClientState*)client;
+    CARLA_SAFE_ASSERT_RETURN(jclient != nullptr, nullptr);
 
     static const char* capture_1  = "system:capture_1";
     static const char* capture_2  = "system:capture_2";
@@ -71,23 +74,20 @@ const char** jack_get_ports(jack_client_t*, const char* a, const char* b, unsign
 }
 
 CARLA_EXPORT
-jack_port_t* jack_port_by_name(jack_client_t* /*client*/, const char* name)
+jack_port_t* jack_port_by_name(jack_client_t* client, const char* name)
 {
-    carla_stdout("CarlaJackClient :: %s | %s", __FUNCTION__, name);
-
-//     CarlaJackClient* const jclient = (CarlaJackClient*)client;
-//     CARLA_SAFE_ASSERT_RETURN(jclient != nullptr, 0);
+    carla_stdout("%s(%p, %s)", __FUNCTION__, client, name);
 
-//     const JackClientState& jstate(jclient->fState);
-    //CARLA_SAFE_ASSERT_RETURN(jstate.activated, 0);
+    JackClientState* const jclient = (JackClientState*)client;
+    CARLA_SAFE_ASSERT_RETURN(jclient != nullptr, 0);
 
     static const JackPortState capturePorts[] = {
-        JackPortState("system", "capture_1", 0, JackPortIsOutput|JackPortIsPhysical|JackPortIsTerminal, true),
-        JackPortState("system", "capture_2", 1, JackPortIsOutput|JackPortIsPhysical|JackPortIsTerminal, true),
+        JackPortState("system", "capture_1", 0, JackPortIsOutput|JackPortIsPhysical|JackPortIsTerminal, false, true),
+        JackPortState("system", "capture_2", 1, JackPortIsOutput|JackPortIsPhysical|JackPortIsTerminal, false, true),
     };
     static const JackPortState playbackPorts[] = {
-        JackPortState("system", "playback_1", 3, JackPortIsInput|JackPortIsPhysical|JackPortIsTerminal, true),
-        JackPortState("system", "playback_2", 4, JackPortIsInput|JackPortIsPhysical|JackPortIsTerminal, true),
+        JackPortState("system", "playback_1", 3, JackPortIsInput|JackPortIsPhysical|JackPortIsTerminal, false, true),
+        JackPortState("system", "playback_2", 4, JackPortIsInput|JackPortIsPhysical|JackPortIsTerminal, false, true),
     };
 
     if (std::strncmp(name, "system:", 7) == 0)
@@ -124,9 +124,9 @@ jack_port_t* jack_port_by_name(jack_client_t* /*client*/, const char* name)
 }
 
 CARLA_EXPORT
-jack_port_t* jack_port_by_id(jack_client_t*, jack_port_id_t)
+jack_port_t* jack_port_by_id(jack_client_t* client, jack_port_id_t port_id)
 {
-    carla_stdout("CarlaJackClient :: %s", __FUNCTION__);
+    carla_stderr2("%s(%p, %u)", __FUNCTION__, client, port_id);
 
     return nullptr;
 }
diff --git a/source/libjack/libjack_ports.cpp b/source/libjack/libjack_ports.cpp
index 77dfce9ad..fdc6d0773 100644
--- a/source/libjack/libjack_ports.cpp
+++ b/source/libjack/libjack_ports.cpp
@@ -23,9 +23,9 @@ CARLA_BACKEND_USE_NAMESPACE
 
 CARLA_EXPORT
 jack_port_t* jack_port_register(jack_client_t* client, const char* port_name, const char* port_type,
-                                unsigned long flags, unsigned long /*buffer_size*/)
+                                unsigned long flags, unsigned long buffer_size)
 {
-    carla_stdout("CarlaJackClient :: %s | %s %s %lu", __FUNCTION__, port_name, port_type, flags);
+    carla_stdout("%s(%p, %s, %s, 0x%lx, %lu)", __FUNCTION__, client, port_name, port_type, flags, buffer_size);
 
     JackClientState* const jclient = (JackClientState*)client;
     CARLA_SAFE_ASSERT_RETURN(jclient != nullptr, nullptr);
@@ -37,7 +37,7 @@ jack_port_t* jack_port_register(jack_client_t* client, const char* port_name, co
     {
         if (flags & JackPortIsInput)
         {
-            JackPortState* const port = new JackPortState(jclient->name, port_name, jclient->audioIns.count(), flags, false);
+            JackPortState* const port = new JackPortState(jclient->name, port_name, jclient->audioIns.count(), flags, false, false);
 
             const CarlaMutexLocker cms(jclient->mutex);
 
@@ -47,7 +47,7 @@ jack_port_t* jack_port_register(jack_client_t* client, const char* port_name, co
 
         if (flags & JackPortIsOutput)
         {
-            JackPortState* const port = new JackPortState(jclient->name, port_name, jclient->audioOuts.count(), flags, false);
+            JackPortState* const port = new JackPortState(jclient->name, port_name, jclient->audioOuts.count(), flags, false, false);
 
             const CarlaMutexLocker cms(jclient->mutex);
 
@@ -59,6 +59,32 @@ jack_port_t* jack_port_register(jack_client_t* client, const char* port_name, co
         return nullptr;
     }
 
+    if (std::strcmp(port_type, JACK_DEFAULT_MIDI_TYPE) == 0)
+    {
+        if (flags & JackPortIsInput)
+        {
+            JackPortState* const port = new JackPortState(jclient->name, port_name, jclient->midiIns.count(), flags, true, false);
+
+            const CarlaMutexLocker cms(jclient->mutex);
+
+            jclient->midiIns.append(port);
+            return (jack_port_t*)port;
+        }
+
+        if (flags & JackPortIsOutput)
+        {
+            JackPortState* const port = new JackPortState(jclient->name, port_name, jclient->midiOuts.count(), flags, true, false);
+
+            const CarlaMutexLocker cms(jclient->mutex);
+
+            jclient->midiOuts.append(port);
+            return (jack_port_t*)port;
+        }
+
+        carla_stderr2("Invalid port flags '%x'", flags);
+        return nullptr;
+    }
+
     carla_stderr2("Invalid port type '%s'", port_type);
     return nullptr;
 }
@@ -66,6 +92,8 @@ jack_port_t* jack_port_register(jack_client_t* client, const char* port_name, co
 CARLA_EXPORT
 int jack_port_unregister(jack_client_t* client, jack_port_t* port)
 {
+    carla_stdout("%s(%p, %p)", __FUNCTION__, client, port);
+
     JackClientState* const jclient = (JackClientState*)client;
     CARLA_SAFE_ASSERT_RETURN(jclient != nullptr, 1);
 
@@ -75,19 +103,36 @@ int jack_port_unregister(jack_client_t* client, jack_port_t* port)
 
     const CarlaMutexLocker cms(jclient->mutex);
 
-    if (jport->flags & JackPortIsInput)
+    if (jport->isMidi)
     {
-        CARLA_SAFE_ASSERT_RETURN(jclient->audioIns.removeOne(jport), 1);
-        return 0;
-    }
+        if (jport->flags & JackPortIsInput)
+        {
+            CARLA_SAFE_ASSERT_RETURN(jclient->midiIns.removeOne(jport), 1);
+            return 0;
+        }
 
-    if (jport->flags & JackPortIsOutput)
+        if (jport->flags & JackPortIsOutput)
+        {
+            CARLA_SAFE_ASSERT_RETURN(jclient->midiOuts.removeOne(jport), 1);
+            return 0;
+        }
+    }
+    else
     {
-        CARLA_SAFE_ASSERT_RETURN(jclient->audioOuts.removeOne(jport), 1);
-        return 0;
+        if (jport->flags & JackPortIsInput)
+        {
+            CARLA_SAFE_ASSERT_RETURN(jclient->audioIns.removeOne(jport), 1);
+            return 0;
+        }
+
+        if (jport->flags & JackPortIsOutput)
+        {
+            CARLA_SAFE_ASSERT_RETURN(jclient->audioOuts.removeOne(jport), 1);
+            return 0;
+        }
     }
 
-    carla_stderr2("Invalid port type on unregister");
+    carla_stderr2("Invalid port on unregister");
     return 1;
 }
 
@@ -103,9 +148,9 @@ void* jack_port_get_buffer(jack_port_t* port, jack_nframes_t)
 // --------------------------------------------------------------------------------------------------------------------
 
 CARLA_EXPORT
-jack_uuid_t jack_port_uuid(const jack_port_t*)
+jack_uuid_t jack_port_uuid(const jack_port_t* port)
 {
-    carla_stdout("CarlaJackClient :: %s", __FUNCTION__);
+    carla_stdout("%s(%p)", __FUNCTION__, port);
 
     return 0;
 }
@@ -113,7 +158,7 @@ jack_uuid_t jack_port_uuid(const jack_port_t*)
 CARLA_EXPORT
 const char* jack_port_name(const jack_port_t* port)
 {
-    carla_stdout("CarlaJackClient :: %s", __FUNCTION__);
+    carla_stdout("%s(%p)", __FUNCTION__, port);
 
     JackPortState* const jport = (JackPortState*)port;
     CARLA_SAFE_ASSERT_RETURN(jport != nullptr, nullptr);
@@ -124,7 +169,7 @@ const char* jack_port_name(const jack_port_t* port)
 CARLA_EXPORT
 const char* jack_port_short_name(const jack_port_t* port)
 {
-    carla_stdout("CarlaJackClient :: %s", __FUNCTION__);
+    carla_stdout("%s(%p)", __FUNCTION__, port);
 
     JackPortState* const jport = (JackPortState*)port;
     CARLA_SAFE_ASSERT_RETURN(jport != nullptr, nullptr);
@@ -135,7 +180,7 @@ const char* jack_port_short_name(const jack_port_t* port)
 CARLA_EXPORT
 int jack_port_flags(const jack_port_t* port)
 {
-    carla_stdout("CarlaJackClient :: %s", __FUNCTION__);
+    carla_stdout("%s(%p)", __FUNCTION__, port);
 
     JackPortState* const jport = (JackPortState*)port;
     CARLA_SAFE_ASSERT_RETURN(jport != nullptr, 0);
@@ -146,44 +191,69 @@ int jack_port_flags(const jack_port_t* port)
 CARLA_EXPORT
 const char* jack_port_type(const jack_port_t* port)
 {
-    carla_stdout("CarlaJackClient :: %s", __FUNCTION__);
+    carla_stdout("%s(%p)", __FUNCTION__, port);
 
     JackPortState* const jport = (JackPortState*)port;
     CARLA_SAFE_ASSERT_RETURN(jport != nullptr, nullptr);
 
-    // TODO
+    static const char* const kAudioType = JACK_DEFAULT_AUDIO_TYPE;
+    static const char* const kMidiType  = JACK_DEFAULT_MIDI_TYPE;
 
-    return JACK_DEFAULT_AUDIO_TYPE;
+    return jport->isMidi ? kMidiType : kAudioType;
 }
 
-//jack_port_type_id_t jack_port_type_id (const jack_port_t *port) JACK_OPTIONAL_WEAK_EXPORT;
+CARLA_EXPORT
+uint32_t jack_port_type_id(const jack_port_t* port)
+{
+    carla_stdout("%s(%p)", __FUNCTION__, port);
+
+    JackPortState* const jport = (JackPortState*)port;
+    CARLA_SAFE_ASSERT_RETURN(jport != nullptr, 0);
+
+    return jport->isMidi ? 1 : 0;
+}
 
 // --------------------------------------------------------------------------------------------------------------------
 
-//int jack_port_is_mine (const jack_client_t *client, const jack_port_t *port) JACK_OPTIONAL_WEAK_EXPORT;
+CARLA_EXPORT
+int jack_port_is_mine(const jack_client_t* client, const jack_port_t* port)
+{
+    carla_stderr2("%s(%p, %p)", __FUNCTION__, client, port);
+
+    return 0;
+}
 
 CARLA_EXPORT
-int jack_port_connected(const jack_port_t*)
+int jack_port_connected(const jack_port_t* port)
 {
-    carla_stdout("CarlaJackClient :: %s", __FUNCTION__);
+    carla_stderr2("%s(%p)", __FUNCTION__, port);
 
     return 1;
 }
 
-//int jack_port_connected_to (const jack_port_t *port,
-//                            const char *port_name) JACK_OPTIONAL_WEAK_EXPORT;
+CARLA_EXPORT
+int jack_port_connected_to(const jack_port_t* port, const char* port_name)
+{
+    carla_stderr2("%s(%p, %s)", __FUNCTION__, port, port_name);
+
+    return 1;
+}
 
 // --------------------------------------------------------------------------------------------------------------------
 
 CARLA_EXPORT
-const char** jack_port_get_connections (const jack_port_t*)
+const char** jack_port_get_connections (const jack_port_t* port)
 {
+    carla_stderr2("%s(%p)", __FUNCTION__, port);
+
     return nullptr;
 }
 
 CARLA_EXPORT
-const char** jack_port_get_all_connections(const jack_client_t*, const jack_port_t*)
+const char** jack_port_get_all_connections(const jack_client_t* client, const jack_port_t* port)
 {
+    carla_stderr2("%s(%p, %p)", __FUNCTION__, client, port);
+
     return nullptr;
 }
 
@@ -219,25 +289,25 @@ const char** jack_port_get_all_connections(const jack_client_t*, const jack_port
 // --------------------------------------------------------------------------------------------------------------------
 
 CARLA_EXPORT
-int jack_connect(jack_client_t*, const char*, const char*)
+int jack_connect(jack_client_t* client, const char* a, const char* b)
 {
-    carla_stdout("CarlaJackClient :: %s", __FUNCTION__);
+    carla_stderr2("%s(%p, %s. %s)", __FUNCTION__, client, a, b);
 
     return 0;
 }
 
 CARLA_EXPORT
-int jack_disconnect(jack_client_t*, const char*, const char*)
+int jack_disconnect(jack_client_t* client, const char* a, const char* b)
 {
-    carla_stdout("CarlaJackClient :: %s", __FUNCTION__);
+    carla_stderr2("%s(%p, %s. %s)", __FUNCTION__, client, a, b);
 
     return 0;
 }
 
 CARLA_EXPORT
-int jack_port_disconnect(jack_client_t*, jack_port_t*)
+int jack_port_disconnect(jack_client_t* client, jack_port_t* port)
 {
-    carla_stdout("CarlaJackClient :: %s", __FUNCTION__);
+    carla_stderr2("%s(%p, %p)", __FUNCTION__, client, port);
 
     return 0;
 }
diff --git a/source/libjack/libjack_transport.cpp b/source/libjack/libjack_transport.cpp
index 9db085048..872ef59c9 100644
--- a/source/libjack/libjack_transport.cpp
+++ b/source/libjack/libjack_transport.cpp
@@ -15,7 +15,6 @@
  * For a full copy of the GNU General Public License see the doc/GPL.txt file.
  */
 
-// need to include this first
 #include "libjack.hpp"
 
 CARLA_BACKEND_USE_NAMESPACE
@@ -23,16 +22,28 @@ CARLA_BACKEND_USE_NAMESPACE
 // --------------------------------------------------------------------------------------------------------------------
 
 CARLA_EXPORT
-int jack_engine_takeover_timebase(jack_client_t*)
+int jack_engine_takeover_timebase(jack_client_t* client)
 {
+    carla_stdout("%s(%p)", __FUNCTION__, client);
+
     return ENOSYS;
 }
 
-// int  jack_release_timebase (jack_client_t *client) JACK_OPTIONAL_WEAK_EXPORT;
+// --------------------------------------------------------------------------------------------------------------------
+
+CARLA_EXPORT
+int jack_release_timebase(jack_client_t* client)
+{
+    carla_stdout("%s(%p)", __FUNCTION__, client);
+
+    return 0;
+}
 
 CARLA_EXPORT
 int jack_set_sync_callback(jack_client_t* client, JackSyncCallback callback, void* arg)
 {
+    carla_stdout("%s(%p, %p, %p)", __FUNCTION__, client, callback, arg);
+
     JackClientState* const jclient = (JackClientState*)client;
     CARLA_SAFE_ASSERT_RETURN(jclient != nullptr, 1);
 
@@ -43,21 +54,28 @@ int jack_set_sync_callback(jack_client_t* client, JackSyncCallback callback, voi
     return 0;
 }
 
-// int  jack_set_sync_timeout (jack_client_t *client,
-//                             jack_time_t timeout) JACK_OPTIONAL_WEAK_EXPORT;
+CARLA_EXPORT
+int jack_set_sync_timeout(jack_client_t* client, jack_time_t timeout)
+{
+    carla_stdout("%s(%p, " P_UINT64 ")", __FUNCTION__, client, timeout);
+
+    return 0;
+}
 
 CARLA_EXPORT
-int jack_set_timebase_callback(jack_client_t*, int, JackTimebaseCallback, void*)
+int jack_set_timebase_callback(jack_client_t* client, int conditional, JackTimebaseCallback callback, void* arg)
 {
-    // FIXME?
+    carla_stdout("%s(%p, %i, %p, %p)", __FUNCTION__, client, conditional, callback, arg);
+
     return EBUSY;
 }
 
 CARLA_EXPORT
-int jack_transport_locate(jack_client_t*, jack_nframes_t)
+int jack_transport_locate(jack_client_t* client, jack_nframes_t frame)
 {
-    // FIXME?
-    return 1;
+    carla_stdout("%s(%p, %u)", __FUNCTION__, client, frame);
+
+    return ENOSYS;
 }
 
 CARLA_EXPORT
@@ -79,6 +97,7 @@ jack_transport_state_t jack_transport_query(const jack_client_t* client, jack_po
     return JackTransportStopped;
 }
 
+CARLA_EXPORT
 jack_nframes_t jack_get_current_transport_frame(const jack_client_t* client)
 {
     if (const JackClientState* const jclient = (JackClientState*)client)
@@ -88,31 +107,37 @@ jack_nframes_t jack_get_current_transport_frame(const jack_client_t* client)
 }
 
 CARLA_EXPORT
-int jack_transport_reposition(jack_client_t*, const jack_position_t*)
+int jack_transport_reposition(jack_client_t* client, const jack_position_t* pos)
 {
-    carla_stdout("CarlaJackClient :: %s", __FUNCTION__);
+    carla_stdout("%s(%p, %p)", __FUNCTION__, client, pos);
 
-    return EINVAL;
+    return ENOSYS;
 }
 
 CARLA_EXPORT
-void jack_transport_start(jack_client_t*)
+void jack_transport_start(jack_client_t* client)
 {
-    carla_stdout("CarlaJackClient :: %s", __FUNCTION__);
-
+    carla_stdout("%s(%p)", __FUNCTION__, client);
 }
 
 CARLA_EXPORT
-void jack_transport_stop (jack_client_t*)
+void jack_transport_stop(jack_client_t* client)
 {
-    carla_stdout("CarlaJackClient :: %s", __FUNCTION__);
-
+    carla_stdout("%s(%p)", __FUNCTION__, client);
 }
 
-// void jack_get_transport_info (jack_client_t *client,
-//                               jack_transport_info_t *tinfo) JACK_OPTIONAL_WEAK_EXPORT;
+// --------------------------------------------------------------------------------------------------------------------
+
+CARLA_EXPORT
+void jack_get_transport_info(jack_client_t* client, void* tinfo)
+{
+    carla_stdout("%s(%p, %p)", __FUNCTION__, client, tinfo);
+}
 
-// void jack_set_transport_info (jack_client_t *client,
-//                               jack_transport_info_t *tinfo) JACK_OPTIONAL_WEAK_EXPORT;
+CARLA_EXPORT
+void jack_set_transport_info(jack_client_t* client, void* tinfo)
+{
+    carla_stdout("%s(%p, %p)", __FUNCTION__, client, tinfo);
+}
 
 // --------------------------------------------------------------------------------------------------------------------