diff --git a/modules/juce_audio_formats/codecs/juce_AiffAudioFormat.cpp b/modules/juce_audio_formats/codecs/juce_AiffAudioFormat.cpp
index 186ed1ad0e..0d6a748e7c 100644
--- a/modules/juce_audio_formats/codecs/juce_AiffAudioFormat.cpp
+++ b/modules/juce_audio_formats/codecs/juce_AiffAudioFormat.cpp
@@ -983,12 +983,17 @@ AudioFormatReader* AiffAudioFormat::createReaderFor (InputStream* sourceStream,
 
 MemoryMappedAudioFormatReader* AiffAudioFormat::createMemoryMappedReader (const File& file)
 {
-    if (FileInputStream* fin = file.createInputStream())
+    return createMemoryMappedReader (file.createInputStream());
+}
+
+MemoryMappedAudioFormatReader* AiffAudioFormat::createMemoryMappedReader (FileInputStream* fin)
+{
+    if (fin != nullptr)
     {
         AiffAudioFormatReader reader (fin);
 
         if (reader.lengthInSamples > 0)
-            return new MemoryMappedAiffReader (file, reader);
+            return new MemoryMappedAiffReader (fin->getFile(), reader);
     }
 
     return nullptr;
diff --git a/modules/juce_audio_formats/codecs/juce_AiffAudioFormat.h b/modules/juce_audio_formats/codecs/juce_AiffAudioFormat.h
index fe475e31e9..9895d1b6e9 100644
--- a/modules/juce_audio_formats/codecs/juce_AiffAudioFormat.h
+++ b/modules/juce_audio_formats/codecs/juce_AiffAudioFormat.h
@@ -70,7 +70,8 @@ public:
     AudioFormatReader* createReaderFor (InputStream* sourceStream,
                                         bool deleteStreamIfOpeningFails) override;
 
-    MemoryMappedAudioFormatReader* createMemoryMappedReader (const File&) override;
+    MemoryMappedAudioFormatReader* createMemoryMappedReader (const File&)      override;
+    MemoryMappedAudioFormatReader* createMemoryMappedReader (FileInputStream*) override;
 
     AudioFormatWriter* createWriterFor (OutputStream* streamToWriteTo,
                                         double sampleRateToUse,
diff --git a/modules/juce_audio_formats/codecs/juce_WavAudioFormat.cpp b/modules/juce_audio_formats/codecs/juce_WavAudioFormat.cpp
index 52535970f2..d8e75f242a 100644
--- a/modules/juce_audio_formats/codecs/juce_WavAudioFormat.cpp
+++ b/modules/juce_audio_formats/codecs/juce_WavAudioFormat.cpp
@@ -1595,12 +1595,17 @@ AudioFormatReader* WavAudioFormat::createReaderFor (InputStream* sourceStream,
 
 MemoryMappedAudioFormatReader* WavAudioFormat::createMemoryMappedReader (const File& file)
 {
-    if (FileInputStream* fin = file.createInputStream())
+    return createMemoryMappedReader (file.createInputStream());
+}
+
+MemoryMappedAudioFormatReader* WavAudioFormat::createMemoryMappedReader (FileInputStream* fin)
+{
+    if (fin != nullptr)
     {
         WavAudioFormatReader reader (fin);
 
         if (reader.lengthInSamples > 0)
-            return new MemoryMappedWavReader (file, reader);
+            return new MemoryMappedWavReader (fin->getFile(), reader);
     }
 
     return nullptr;
diff --git a/modules/juce_audio_formats/codecs/juce_WavAudioFormat.h b/modules/juce_audio_formats/codecs/juce_WavAudioFormat.h
index 5b63f283e7..479e58bb0c 100644
--- a/modules/juce_audio_formats/codecs/juce_WavAudioFormat.h
+++ b/modules/juce_audio_formats/codecs/juce_WavAudioFormat.h
@@ -183,7 +183,8 @@ public:
     AudioFormatReader* createReaderFor (InputStream* sourceStream,
                                         bool deleteStreamIfOpeningFails) override;
 
-    MemoryMappedAudioFormatReader* createMemoryMappedReader (const File&) override;
+    MemoryMappedAudioFormatReader* createMemoryMappedReader (const File&)      override;
+    MemoryMappedAudioFormatReader* createMemoryMappedReader (FileInputStream*) override;
 
     AudioFormatWriter* createWriterFor (OutputStream* streamToWriteTo,
                                         double sampleRateToUse,
diff --git a/modules/juce_audio_formats/format/juce_AudioFormat.cpp b/modules/juce_audio_formats/format/juce_AudioFormat.cpp
index fc3f9ff178..0bbc6e5209 100644
--- a/modules/juce_audio_formats/format/juce_AudioFormat.cpp
+++ b/modules/juce_audio_formats/format/juce_AudioFormat.cpp
@@ -54,3 +54,9 @@ MemoryMappedAudioFormatReader* AudioFormat::createMemoryMappedReader (const File
 {
     return nullptr;
 }
+
+MemoryMappedAudioFormatReader* AudioFormat::createMemoryMappedReader (FileInputStream* fin)
+{
+    delete fin;
+    return nullptr;
+}
diff --git a/modules/juce_audio_formats/format/juce_AudioFormat.h b/modules/juce_audio_formats/format/juce_AudioFormat.h
index fee1e06797..4eb34535ca 100644
--- a/modules/juce_audio_formats/format/juce_AudioFormat.h
+++ b/modules/juce_audio_formats/format/juce_AudioFormat.h
@@ -112,6 +112,7 @@ public:
         If the format does not support this, the method will return nullptr;
     */
     virtual MemoryMappedAudioFormatReader* createMemoryMappedReader (const File& file);
+    virtual MemoryMappedAudioFormatReader* createMemoryMappedReader (FileInputStream* fin);
 
     /** Tries to create an object that can write to a stream with this audio format.