diff --git a/modules/juce_core/text/juce_Base64.cpp b/modules/juce_core/text/juce_Base64.cpp
index 59eaa779e7..101a5e1659 100644
--- a/modules/juce_core/text/juce_Base64.cpp
+++ b/modules/juce_core/text/juce_Base64.cpp
@@ -137,7 +137,7 @@ public:
         MemoryOutputStream m;
 
         for (int i = r.nextInt (400); --i >= 0;)
-            m.writeByte (r.nextInt (256));
+            m.writeByte ((char) r.nextInt (256));
 
         return m.getMemoryBlock();
     }