diff --git a/modules/juce_audio_processors/format_types/juce_VSTPluginFormat.cpp b/modules/juce_audio_processors/format_types/juce_VSTPluginFormat.cpp
index 9e5418e0fa..44eb9444ad 100644
--- a/modules/juce_audio_processors/format_types/juce_VSTPluginFormat.cpp
+++ b/modules/juce_audio_processors/format_types/juce_VSTPluginFormat.cpp
@@ -1596,7 +1596,9 @@ private:
     {
         BusesProperties returnValue;
 
-        VstSpeakerConfiguration* inArr = nullptr, *outArr = nullptr;
+        HeapBlock<VstSpeakerConfiguration> inArrBlock (1, true), outArrBlock (1, true);
+
+        VstSpeakerConfiguration* inArr = inArrBlock.getData(), *outArr = outArrBlock.getData();
         if (effect->dispatchFunction (effect, plugInOpcodeGetSpeakerArrangement, 0, reinterpret_cast<pointer_sized_int> (&inArr), &outArr, 0.0f) == 0)
             inArr = outArr = nullptr;