diff --git a/src/Sound/VoiceSynthesizer.cxx b/src/Sound/VoiceSynthesizer.cxx
index befb0adbf..7ae061214 100644
--- a/src/Sound/VoiceSynthesizer.cxx
+++ b/src/Sound/VoiceSynthesizer.cxx
@@ -123,7 +123,11 @@ SGSoundSample * FLITEVoiceSynthesizer::synthesize(const std::string & text, doub
   ALsizei rate, count;
   if ( FALSE == Flite_HTS_Engine_synthesize_samples_mono16(_engine, text.c_str(), &data, &count, &rate)) return NULL;
 
-  return new SGSoundSample(&data,
+  auto buf = std::unique_ptr<unsigned char, decltype(free)*>{
+    reinterpret_cast<unsigned char*>( data ),
+    free
+  };
+  return new SGSoundSample(buf,
                            count * sizeof(short),
                            rate,
                            SG_SAMPLE_MONO16);
diff --git a/src/Sound/beacon.cxx b/src/Sound/beacon.cxx
index 46f0013a4..90dcf0074 100644
--- a/src/Sound/beacon.cxx
+++ b/src/Sound/beacon.cxx
@@ -43,24 +43,32 @@ bool FGBeacon::init() {
     unsigned char *ptr;
     size_t i, len;
 
-    const unsigned char* inner_buf = (const unsigned char*)malloc( INNER_SIZE );
-    const unsigned char* middle_buf = (const unsigned char*)malloc(MIDDLE_SIZE);
-    const unsigned char* outer_buf = (const unsigned char*)malloc( OUTER_SIZE );
+    auto inner_buf = std::unique_ptr<unsigned char, decltype(free)*>{
+          reinterpret_cast<unsigned char*>( malloc( INNER_SIZE ) ),
+          free
+    };
+    auto middle_buf = std::unique_ptr<unsigned char, decltype(free)*>{
+          reinterpret_cast<unsigned char*>( malloc( MIDDLE_SIZE ) ),
+          free
+    };
+    auto outer_buf = std::unique_ptr<unsigned char, decltype(free)*>{
+          reinterpret_cast<unsigned char*>( malloc( OUTER_SIZE ) ),
+          free
+    };
 
     // Make inner marker beacon sound
     len= (int)(INNER_DIT_LEN / 2.0 );
     unsigned char inner_dit[INNER_DIT_LEN];
-    make_tone( inner_dit, INNER_FREQ, len, INNER_DIT_LEN,
-	       TRANSITION_BYTES );
+    make_tone( inner_dit, INNER_FREQ, len, INNER_DIT_LEN, TRANSITION_BYTES );
 
-    ptr = (unsigned char*)inner_buf;
+    ptr = inner_buf.get();
     for ( i = 0; i < 6; ++i ) {
 	memcpy( ptr, inner_dit, INNER_DIT_LEN );
 	ptr += INNER_DIT_LEN;
     }
 
     try {
-        inner = new SGSoundSample( &inner_buf, INNER_SIZE, BYTES_PER_SECOND );
+        inner = new SGSoundSample( inner_buf, INNER_SIZE, BYTES_PER_SECOND );
         inner->set_reference_dist( 10.0 );
         inner->set_max_dist( 20.0 );
 
@@ -75,12 +83,12 @@ bool FGBeacon::init() {
         make_tone( middle_dah, MIDDLE_FREQ, len, MIDDLE_DAH_LEN,
 	            TRANSITION_BYTES );
 
-        ptr = (unsigned char*)middle_buf;
+        ptr = (unsigned char*)middle_buf.get();
         memcpy( ptr, middle_dit, MIDDLE_DIT_LEN );
         ptr += MIDDLE_DIT_LEN;
         memcpy( ptr, middle_dah, MIDDLE_DAH_LEN );
 
-        middle = new SGSoundSample( &middle_buf, MIDDLE_SIZE, BYTES_PER_SECOND);
+        middle = new SGSoundSample( middle_buf, MIDDLE_SIZE, BYTES_PER_SECOND);
         middle->set_reference_dist( 10.0 );
         middle->set_max_dist( 20.0 );
 
@@ -89,13 +97,13 @@ bool FGBeacon::init() {
         unsigned char outer_dah[OUTER_DAH_LEN];
         make_tone( outer_dah, OUTER_FREQ, len, OUTER_DAH_LEN,
 	            TRANSITION_BYTES );
-           
-        ptr = (unsigned char*)outer_buf;
+
+        ptr = (unsigned char*)outer_buf.get();
         memcpy( ptr, outer_dah, OUTER_DAH_LEN );
         ptr += OUTER_DAH_LEN;
         memcpy( ptr, outer_dah, OUTER_DAH_LEN );
 
-        outer = new SGSoundSample( &outer_buf, OUTER_SIZE, BYTES_PER_SECOND );
+        outer = new SGSoundSample( outer_buf, OUTER_SIZE, BYTES_PER_SECOND );
         outer->set_reference_dist( 10.0 );
         outer->set_max_dist( 20.0 );
     } catch ( sg_io_exception &e ) {
diff --git a/src/Sound/morse.cxx b/src/Sound/morse.cxx
index 9e4d5eced..ffef13c59 100644
--- a/src/Sound/morse.cxx
+++ b/src/Sound/morse.cxx
@@ -190,10 +190,13 @@ SGSoundSample *FGMorse::make_ident( const std::string& id, const int freq ) {
     length += 2 * SPACE_SIZE;
 
     // 2. Allocate space for the message
-    const unsigned char* buffer = (const unsigned char *)malloc(length);
+    auto buffer = std::unique_ptr<unsigned char, decltype(free)*>{
+          reinterpret_cast<unsigned char*>( malloc( length ) ),
+          free
+    };
 
     // 3. Assemble the message;
-    unsigned char *buf_ptr = (unsigned char*)buffer;
+    unsigned char *buf_ptr = buffer.get();
 
     for ( i = 0; i < (int)id.length(); ++i ) {
 	if ( idptr[i] >= 'A' && idptr[i] <= 'Z' ) {
@@ -232,7 +235,7 @@ SGSoundSample *FGMorse::make_ident( const std::string& id, const int freq ) {
     buf_ptr += SPACE_SIZE;
 
     // 4. create the simple sound and return
-    SGSoundSample *sample = new SGSoundSample( &buffer, length,
+    SGSoundSample *sample = new SGSoundSample( buffer, length,
                                                BYTES_PER_SECOND );
 
     sample->set_reference_dist( 10.0 );