diff --git a/modules/juce_audio_basics/mpe/juce_MPESynthesiser.cpp b/modules/juce_audio_basics/mpe/juce_MPESynthesiser.cpp
index 2cf1cce626..ac519c494b 100644
--- a/modules/juce_audio_basics/mpe/juce_MPESynthesiser.cpp
+++ b/modules/juce_audio_basics/mpe/juce_MPESynthesiser.cpp
@@ -202,8 +202,15 @@ MPESynthesiserVoice* MPESynthesiser::findVoiceToSteal (MPENote noteToStealVoiceF
         jassert (voice->isActive()); // We wouldn't be here otherwise
 
         usableVoices.add (voice);
-        std::sort (usableVoices.begin(), usableVoices.end(),
-                   [] (const MPESynthesiserVoice* a, const MPESynthesiserVoice* b) { return a->wasStartedBefore (*b); });
+
+        // NB: Using a functor rather than a lambda here due to scare-stories about
+        // compilers generating code containing heap allocations..
+        struct Sorter
+        {
+            bool operator() (const MPESynthesiserVoice* a, const MPESynthesiserVoice* b) const noexcept { return a->wasStartedBefore (*b); }
+        };
+
+        std::sort (usableVoices.begin(), usableVoices.end(), Sorter());
 
         if (! voice->isPlayingButReleased()) // Don't protect released notes
         {
diff --git a/modules/juce_audio_basics/synthesisers/juce_Synthesiser.cpp b/modules/juce_audio_basics/synthesisers/juce_Synthesiser.cpp
index 36c814f561..fa047d1496 100644
--- a/modules/juce_audio_basics/synthesisers/juce_Synthesiser.cpp
+++ b/modules/juce_audio_basics/synthesisers/juce_Synthesiser.cpp
@@ -514,8 +514,15 @@ SynthesiserVoice* Synthesiser::findVoiceToSteal (SynthesiserSound* soundToPlay,
             jassert (voice->isVoiceActive()); // We wouldn't be here otherwise
 
             usableVoices.add (voice);
-            std::sort (usableVoices.begin(), usableVoices.end(),
-                       [] (const SynthesiserVoice* a, const SynthesiserVoice* b) { return a->wasStartedBefore (*b); });
+
+            // NB: Using a functor rather than a lambda here due to scare-stories about
+            // compilers generating code containing heap allocations..
+            struct Sorter
+            {
+                bool operator() (const SynthesiserVoice* a, const SynthesiserVoice* b) const noexcept { return a->wasStartedBefore (*b); }
+            };
+
+            std::sort (usableVoices.begin(), usableVoices.end(), Sorter());
 
             if (! voice->isPlayingButReleased()) // Don't protect released notes
             {