diff --git a/modules/juce_audio_plugin_client/VST3/juce_VST3_Wrapper.cpp b/modules/juce_audio_plugin_client/VST3/juce_VST3_Wrapper.cpp
index b59e9e6bfed5..745df8d1c1c4 100644
--- a/modules/juce_audio_plugin_client/VST3/juce_VST3_Wrapper.cpp
+++ b/modules/juce_audio_plugin_client/VST3/juce_VST3_Wrapper.cpp
@@ -1632,10 +1632,6 @@ class JuceVST3Component : public Vst::IComponent,
             MidiEventList::toMidiBuffer (midiBuffer, *data.inputEvents);
        #endif
 
-       #if JUCE_DEBUG && ! JucePlugin_ProducesMidiOutput
-        const int numMidiEventsComingIn = midiBuffer.getNumEvents();
-       #endif
-
         if (getHostType().isWavelab())
         {
             const int numInputChans  = (data.inputs  != nullptr && data.inputs[0].channelBuffers32 != nullptr)  ? (int) data.inputs[0].numChannels  : 0;
@@ -1653,22 +1649,6 @@ class JuceVST3Component : public Vst::IComponent,
        #if JucePlugin_ProducesMidiOutput
         if (data.outputEvents != nullptr)
             MidiEventList::toEventList (*data.outputEvents, midiBuffer);
-       #elif JUCE_DEBUG
-        /*  This assertion is caused when you've added some events to the
-            midiMessages array in your processBlock() method, which usually means
-            that you're trying to send them somewhere. But in this case they're
-            getting thrown away.
-
-            If your plugin does want to send MIDI messages, you'll need to set
-            the JucePlugin_ProducesMidiOutput macro to 1 in your
-            JucePluginCharacteristics.h file.
-
-            If you don't want to produce any MIDI output, then you should clear the
-            midiMessages array at the end of your processBlock() method, to
-            indicate that you don't want any of the events to be passed through
-            to the output.
-        */
-        jassert (midiBuffer.getNumEvents() <= numMidiEventsComingIn);
        #endif
 
         return kResultTrue;
@@ -1722,7 +1702,8 @@ class JuceVST3Component : public Vst::IComponent,
                     const int numChans = jmin ((int) data.inputs[bus].numChannels, plugInInputChannels - totalInputChans);
 
                     for (int i = 0; i < numChans; ++i)
-                        channelList.set (totalInputChans++, busChannels[i]);
+                        if (busChannels[i] != nullptr)
+                            channelList.set (totalInputChans++, busChannels[i]);
                 }
             }
         }
@@ -1739,13 +1720,16 @@ class JuceVST3Component : public Vst::IComponent,
 
                     for (int i = 0; i < numChans; ++i)
                     {
-                        if (totalOutputChans >= totalInputChans)
+                        if (busChannels[i] != nullptr)
                         {
-                            FloatVectorOperations::clear (busChannels[i], data.numSamples);
-                            channelList.set (totalOutputChans, busChannels[i]);
-                        }
+                            if (totalOutputChans >= totalInputChans)
+                            {
+                                FloatVectorOperations::clear (busChannels[i], data.numSamples);
+                                channelList.set (totalOutputChans, busChannels[i]);
+                            }
 
-                        ++totalOutputChans;
+                            ++totalOutputChans;
+                        }
                     }
                 }
             }
@@ -1764,6 +1748,10 @@ class JuceVST3Component : public Vst::IComponent,
             if (data.inputParameterChanges != nullptr)
                 processParameterChanges (*data.inputParameterChanges);
 
+           #if JUCE_DEBUG && ! JucePlugin_ProducesMidiOutput
+            const int numMidiEventsComingIn = midiBuffer.getNumEvents ();
+           #endif
+
             if (pluginInstance->isSuspended())
             {
                 buffer.clear();
@@ -1779,6 +1767,24 @@ class JuceVST3Component : public Vst::IComponent,
                         pluginInstance->processBlock (buffer, midiBuffer);
                 }
             }
+
+           #if JUCE_DEBUG && (! JucePlugin_ProducesMidiOutput)
+            /*  This assertion is caused when you've added some events to the
+                midiMessages array in your processBlock() method, which usually means
+                that you're trying to send them somewhere. But in this case they're
+                getting thrown away.
+
+                If your plugin does want to send MIDI messages, you'll need to set
+                the JucePlugin_ProducesMidiOutput macro to 1 in your
+                JucePluginCharacteristics.h file.
+
+                If you don't want to produce any MIDI output, then you should clear the
+                midiMessages array at the end of your processBlock() method, to
+                indicate that you don't want any of the events to be passed through
+                to the output.
+            */
+            jassert (midiBuffer.getNumEvents() <= numMidiEventsComingIn);
+           #endif
         }
 
         if (data.outputs != nullptr)
@@ -1793,9 +1799,9 @@ class JuceVST3Component : public Vst::IComponent,
 
                     for (int i = 0; i < numChans; ++i)
                     {
-                        if (outChanIndex < totalInputChans)
+                        if (outChanIndex < totalInputChans && busChannels[i] != nullptr)
                             FloatVectorOperations::copy (busChannels[i], buffer.getReadPointer (outChanIndex), (int) data.numSamples);
-                        else if (outChanIndex >= totalOutputChans)
+                        else if (outChanIndex >= totalOutputChans && busChannels[i] != nullptr)
                             FloatVectorOperations::clear (busChannels[i], (int) data.numSamples);
 
                         ++outChanIndex;