diff --git a/src/NoteTrack.cpp b/src/NoteTrack.cpp
index 22582919f..5e6f97d82 100644
--- a/src/NoteTrack.cpp
+++ b/src/NoteTrack.cpp
@@ -110,7 +110,6 @@ Track(projDirManager)
    SetName(GetDefaultName());
 
    mSeq = NULL;
-   mSerializationBuffer = NULL;
    mSerializationLength = 0;
 
 #ifdef EXPERIMENTAL_MIDI_OUT
@@ -125,9 +124,6 @@ Track(projDirManager)
 
 NoteTrack::~NoteTrack()
 {
-   if (mSerializationBuffer) {
-      delete [] mSerializationBuffer;
-   }
 }
 
 Track::Holder NoteTrack::Duplicate() const
@@ -143,13 +139,15 @@ Track::Holder NoteTrack::Duplicate() const
       SonifyBeginSerialize();
       assert(!mSerializationBuffer);
       // serialize from this to duplicate's mSerializationBuffer
-      mSeq->serialize((void**)&duplicate->mSerializationBuffer,
+      void *buffer;
+      mSeq->serialize(&buffer,
                       &duplicate->mSerializationLength);
+      duplicate->mSerializationBuffer.reset( (char*)buffer );
       SonifyEndSerialize();
    } else if (mSerializationBuffer) {
       SonifyBeginUnserialize();
       assert(!mSeq);
-      std::unique_ptr<Alg_track> alg_track{ Alg_seq::unserialize(mSerializationBuffer,
+      std::unique_ptr<Alg_track> alg_track{ Alg_seq::unserialize(mSerializationBuffer.get(),
                                                       mSerializationLength) };
       assert(alg_track->get_type() == 's');
       duplicate->mSeq.reset(static_cast<Alg_seq*>(alg_track.release()));
@@ -198,9 +196,8 @@ void NoteTrack::WarpAndTransposeNotes(double t0, double t1,
       const auto nt = static_cast<NoteTrack*>(unt.get());
       wxASSERT(!mSeq && nt->mSeq && !nt->mSerializationBuffer);
       // swap mSeq and Buffer between this and nt
-      nt->mSerializationBuffer = mSerializationBuffer;
+      nt->mSerializationBuffer = std::move(mSerializationBuffer);
       nt->mSerializationLength = mSerializationLength;
-      mSerializationBuffer = NULL;
       mSerializationLength = 0;
       mSeq = std::move(nt->mSeq);
    }
diff --git a/src/NoteTrack.h b/src/NoteTrack.h
index c51d7ade7..fafdb6dff 100644
--- a/src/NoteTrack.h
+++ b/src/NoteTrack.h
@@ -198,7 +198,7 @@ class AUDACITY_DLL_API NoteTrack final : public Track {
    // mSeq variable. (TrackArtist should check to make sure this
    // flip-flop from mSeq to mSerializationBuffer happened an
    // even number of times, otherwise mSeq will be NULL).
-   mutable char *mSerializationBuffer; // NULL means no buffer
+   mutable std::unique_ptr<char[]> mSerializationBuffer; // NULL means no buffer
    long mSerializationLength;
 
 #ifdef EXPERIMENTAL_MIDI_OUT
diff --git a/src/TrackArtist.cpp b/src/TrackArtist.cpp
index 6838ae735..e29b0b1f5 100644
--- a/src/TrackArtist.cpp
+++ b/src/TrackArtist.cpp
@@ -2829,12 +2829,11 @@ void TrackArtist::DrawNoteTrack(const NoteTrack *track,
       // JKC: Previously this indirected via seq->, a NULL pointer.
       // This was actually OK, since unserialize is a static function.
       // Alg_seq:: is clearer.
-      std::unique_ptr<Alg_track> alg_track{ Alg_seq::unserialize(track->mSerializationBuffer,
+      std::unique_ptr<Alg_track> alg_track{ Alg_seq::unserialize(track->mSerializationBuffer.get(),
             track->mSerializationLength) };
       assert(alg_track->get_type() == 's');
       const_cast<NoteTrack*>(track)->mSeq.reset(seq = static_cast<Alg_seq*>(alg_track.release()));
-      free(track->mSerializationBuffer);
-      track->mSerializationBuffer = NULL;
+      track->mSerializationBuffer.reset();
    }
    assert(seq);
    int visibleChannels = track->mVisibleChannels;