diff --git a/Makefile b/Makefile
index 2cf6ed6..a820d8a 100644
--- a/Makefile
+++ b/Makefile
@@ -220,6 +220,9 @@ native: carla deps dgl plugins resources
 mini: carla deps dgl mini-plugins mini-resources
 	$(MAKE) mini -C src $(CARLA_EXTRA_ARGS)
 
+au: carla deps dgl plugins resources
+	$(MAKE) au -C src $(CARLA_EXTRA_ARGS)
+
 clap: carla deps dgl plugins resources
 	$(MAKE) clap -C src $(CARLA_EXTRA_ARGS)
 
diff --git a/dpf b/dpf
index 8ac24f8..32ba6c1 160000
--- a/dpf
+++ b/dpf
@@ -1 +1 @@
-Subproject commit 8ac24f80446a0f3d48365e96a31f12fd201fd3ff
+Subproject commit 32ba6c1cb418e6a1d6d97c979e76c8ecab46fbc7
diff --git a/src/Cardinal/DistrhoPluginInfo.h b/src/Cardinal/DistrhoPluginInfo.h
index 18afb2b..200488a 100644
--- a/src/Cardinal/DistrhoPluginInfo.h
+++ b/src/Cardinal/DistrhoPluginInfo.h
@@ -36,6 +36,7 @@
 #define DISTRHO_PLUGIN_AU_TYPE   aumf
 #define DISTRHO_PLUGIN_BRAND_ID  Dstr
 #define DISTRHO_PLUGIN_UNIQUE_ID DcnM
+#define DISTRHO_PLUGIN_EXTRA_IO  { CARDINAL_NUM_AUDIO_INPUTS, CARDINAL_NUM_AUDIO_OUTPUTS }, { 2, 2 }
 
 #ifdef HEADLESS
 #define DISTRHO_PLUGIN_HAS_UI             0
diff --git a/src/CardinalPlugin.cpp b/src/CardinalPlugin.cpp
index 3ed2fe9..4f5acb5 100644
--- a/src/CardinalPlugin.cpp
+++ b/src/CardinalPlugin.cpp
@@ -196,6 +196,14 @@ class CardinalPlugin : public CardinalBasePlugin
     float fMiniReportValues[kCardinalParameterCountAtMini - kCardinalParameterStartMini];
    #endif
 
+   #ifdef DISTRHO_PLUGIN_EXTRA_IO
+    uint16_t fNumActiveInputs = DISTRHO_PLUGIN_NUM_INPUTS;
+    uint16_t fNumActiveOutputs = DISTRHO_PLUGIN_NUM_OUTPUTS;
+   #else
+    static constexpr const uint16_t fNumActiveInputs = DISTRHO_PLUGIN_NUM_INPUTS;
+    static constexpr const uint16_t fNumActiveOutputs = DISTRHO_PLUGIN_NUM_OUTPUTS;
+   #endif
+
 public:
     CardinalPlugin()
         : CardinalBasePlugin(kCardinalParameterCount, 0, kCardinalStateCount),
@@ -1135,7 +1143,10 @@ protected:
        #if DISTRHO_PLUGIN_NUM_INPUTS != 0
         fAudioBufferCopy = new float*[DISTRHO_PLUGIN_NUM_INPUTS];
         for (int i=0; i<DISTRHO_PLUGIN_NUM_INPUTS; ++i)
+        {
             fAudioBufferCopy[i] = new float[context->bufferSize];
+            std::memset(fAudioBufferCopy[i], 0, sizeof(float) * context->bufferSize);
+        }
        #endif
 
         fNextExpectedFrame = 0;
@@ -1226,7 +1237,7 @@ protected:
         else
         {
            #if DISTRHO_PLUGIN_NUM_INPUTS != 0
-            for (int i=0; i<DISTRHO_PLUGIN_NUM_INPUTS; ++i)
+            for (int i=0; i<fNumActiveInputs; ++i)
             {
                #if CARDINAL_VARIANT_MAIN || CARDINAL_VARIANT_MINI
                 // can be null on main and mini variants
@@ -1241,7 +1252,7 @@ protected:
             context->dataOuts = outputs;
         }
 
-        for (int i=0; i<DISTRHO_PLUGIN_NUM_OUTPUTS; ++i)
+        for (int i=0; i<fNumActiveOutputs; ++i)
         {
            #if CARDINAL_VARIANT_MAIN || CARDINAL_VARIANT_MINI
             // can be null on main and mini variants
@@ -1288,6 +1299,14 @@ protected:
         context->engine->setSampleRate(newSampleRate);
     }
 
+   #ifdef DISTRHO_PLUGIN_EXTRA_IO
+    void ioChanged(const uint16_t numInputs, const uint16_t numOutputs) override
+    {
+        fNumActiveInputs = numInputs;
+        fNumActiveOutputs = numOutputs;
+    }
+   #endif
+
     // -------------------------------------------------------------------------------------------------------
 
 private:
diff --git a/src/CardinalUI.cpp b/src/CardinalUI.cpp
index b088e59..c1c01fd 100644
--- a/src/CardinalUI.cpp
+++ b/src/CardinalUI.cpp
@@ -426,10 +426,6 @@ public:
             const double height = std::max(538.f, rack::settings::windowSize.y) * scaleFactor;
             setSize(width, height);
         }
-        else if (scaleFactor != 1.0)
-        {
-            setSize(DISTRHO_UI_DEFAULT_WIDTH * scaleFactor, DISTRHO_UI_DEFAULT_HEIGHT * scaleFactor);
-        }
 
        #if DISTRHO_PLUGIN_WANT_DIRECT_ACCESS
         const DGL_NAMESPACE::Window::ScopedGraphicsContext sgc(window);
@@ -932,7 +928,7 @@ protected:
                 context->patch->loadAutosave();
             } catch(const rack::Exception& e) {
                 d_stderr(e.what());
-            } DISTRHO_SAFE_EXCEPTION_RETURN("setState loadAutosave",);
+            } DISTRHO_SAFE_EXCEPTION_RETURN("stateChanged loadAutosave",);
 
             return;
         }
@@ -1180,7 +1176,7 @@ protected:
         const int height = static_cast<int>(ev.size.getHeight() / scaleFactor + 0.5);
 
         char sizeString[64] = {};
-        std::snprintf(sizeString, sizeof(sizeString), "%d:%d", width, height);
+        std::snprintf(sizeString, sizeof(sizeString) - 1, "%d:%d", width, height);
         setState("windowSize", sizeString);
 
         if (rack::isStandalone())
diff --git a/src/Makefile b/src/Makefile
index 24038a8..0e892e1 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -142,6 +142,10 @@ native: $(TARGETS)
 mini: $(TARGETS)
 	$(MAKE) jack -C CardinalMini
 
+au: $(TARGETS)
+	$(MAKE) au -C CardinalFX $(CARDINAL_SYNTH_ARGS)
+	$(MAKE) au -C CardinalSynth $(CARDINAL_SYNTH_ARGS)
+
 lv2: $(TARGETS)
 	$(MAKE) lv2 -C Cardinal
 	$(MAKE) lv2 -C CardinalFX $(CARDINAL_FX_ARGS)
diff --git a/src/Makefile.cardinal.mk b/src/Makefile.cardinal.mk
index fd4c058..56b3dd9 100644
--- a/src/Makefile.cardinal.mk
+++ b/src/Makefile.cardinal.mk
@@ -412,7 +412,7 @@ BUILD_CXX_FLAGS += -DCARDINAL_PLUGIN_PREFIX='"$(PREFIX)"'
 # Enable all possible plugin types and setup resources
 
 ifeq ($(CARDINAL_VARIANT),main)
-TARGETS = jack lv2 vst3 clap
+TARGETS = clap jack lv2 vst3
 else ifeq ($(DSP_UI_SPLIT),true)
 TARGETS = lv2_sep
 else ifeq ($(CARDINAL_VARIANT),mini)