diff --git a/modules/juce_blocks_basics/topology/juce_PhysicalTopologySource.cpp b/modules/juce_blocks_basics/topology/juce_PhysicalTopologySource.cpp
index 1d2a1ae5c8..f435b5f1ed 100644
--- a/modules/juce_blocks_basics/topology/juce_PhysicalTopologySource.cpp
+++ b/modules/juce_blocks_basics/topology/juce_PhysicalTopologySource.cpp
@@ -247,7 +247,7 @@ struct PhysicalTopologySource::Internal
 
         bool isLockedFromOutside() const override
         {
-            return lockedFromOutside;
+            return lockedFromOutside && ! findDevices().isEmpty();
         }
 
         static bool isBlocksMidiDeviceName (const juce::String& name)