diff --git a/common/JackPhysicalMidiInput.h b/common/JackPhysicalMidiInput.h
index 6ba3b471..a05de6d0 100644
--- a/common/JackPhysicalMidiInput.h
+++ b/common/JackPhysicalMidiInput.h
@@ -120,7 +120,7 @@ namespace Jack {
     public:
 
         JackPhysicalMidiInput(size_t buffer_size=1024);
-        ~JackPhysicalMidiInput();
+        virtual ~JackPhysicalMidiInput();
 
         /**
          * Called to process MIDI data during a period.
diff --git a/common/JackPhysicalMidiOutput.h b/common/JackPhysicalMidiOutput.h
index f76a233a..9b4804b7 100644
--- a/common/JackPhysicalMidiOutput.h
+++ b/common/JackPhysicalMidiOutput.h
@@ -92,7 +92,7 @@ namespace Jack {
 
         JackPhysicalMidiOutput(size_t non_rt_buffer_size=1024,
                                size_t rt_buffer_size=64);
-        ~JackPhysicalMidiOutput();
+        virtual ~JackPhysicalMidiOutput();
 
         /**
          * Called to process MIDI data during a period.