diff --git a/docs/notes.txt b/docs/notes.txt
index 1d7ab80..1f6fd27 100644
--- a/docs/notes.txt
+++ b/docs/notes.txt
@@ -52,3 +52,15 @@ perf record --pid=XXXXX
 - Analyse using https://github.com/KDAB/hotspot
 
 
+
+Memcheck
+--------
+
+To generate memory usage plots in [massif format](https://valgrind.org/docs/manual/ms-manual.html):
+
+    G_SLICE=always-malloc valgrind --tool=massif ./vimix
+
+To check for memory leaks:
+
+    G_SLICE=always-malloc valgrind --leak-check=full --log-file=vimix_mem.txt ./vimix
+
diff --git a/src/Grid.cpp b/src/Grid.cpp
index 7111eec..be6ebb8 100644
--- a/src/Grid.cpp
+++ b/src/Grid.cpp
@@ -34,6 +34,12 @@ Grid::Grid(Group *parent, Shapes s) : active_(false), shape_(s), unit_(UNIT_DEFA
 
 }
 
+Grid::~Grid()
+{
+    if (root_)
+        delete root_;
+}
+
 glm::vec2 Grid::step() const {
 
     if ( shape_ != GRID_POLAR )
diff --git a/src/Grid.h b/src/Grid.h
index 532d88f..6bccf5a 100644
--- a/src/Grid.h
+++ b/src/Grid.h
@@ -15,7 +15,7 @@ public:
     } Shapes;
 
     Grid(Group *parent, Shapes s = GRID_ORTHO);
-    virtual ~Grid() {}
+    virtual ~Grid();
 
     // if active, the view will use it to approximate coordinates
     inline bool active() const { return active_; }
diff --git a/src/GstToolkit.cpp b/src/GstToolkit.cpp
index 72c9637..af51d69 100644
--- a/src/GstToolkit.cpp
+++ b/src/GstToolkit.cpp
@@ -268,13 +268,14 @@ std::string GstToolkit::used_gpu_decoding_plugins(GstElement *gstbin)
         {
             GstElement *e = static_cast<GstElement*>(g_value_peek_pointer(&value));
             if (e) {
-                const gchar *name = gst_element_get_name(e);
+                gchar *name = gst_element_get_name(e);
                 for (int i = 0; i < N; i++) {
                     if (std::string(name).find(plugins[i]) != std::string::npos) {
                         found = plugins[i];
                         break;
                     }
                 }
+                g_free(name);
             }
         }
         g_value_unset(&value);
diff --git a/src/MediaPlayer.cpp b/src/MediaPlayer.cpp
index e0533f9..15cb374 100644
--- a/src/MediaPlayer.cpp
+++ b/src/MediaPlayer.cpp
@@ -747,8 +747,10 @@ void MediaPlayer::Frame::unmap()
 void MediaPlayer::pipeline_terminate( GstElement *p )
 {
 #ifdef MEDIA_PLAYER_DEBUG
-    g_printerr("MediaPlayer %s close\n", gst_element_get_name(p));
-    Log::Info("MediaPlayer %s closed", gst_element_get_name(p));
+    gchar *name = gst_element_get_name(p);
+    g_printerr("MediaPlayer %s close\n", name);
+    Log::Info("MediaPlayer %s closed", name);
+    g_free(name);
 #endif
 
     // end pipeline
diff --git a/src/MousePointer.cpp b/src/MousePointer.cpp
index 26e913f..7a68b7a 100644
--- a/src/MousePointer.cpp
+++ b/src/MousePointer.cpp
@@ -243,3 +243,12 @@ MousePointer::MousePointer() : mode_(Pointer::POINTER_DEFAULT)
     pointer_[Pointer::POINTER_METRONOME] = new PointerMetronome;
 }
 
+MousePointer::~MousePointer()
+{
+    delete pointer_[Pointer::POINTER_DEFAULT];
+    delete pointer_[Pointer::POINTER_GRID];
+    delete pointer_[Pointer::POINTER_LINEAR];
+    delete pointer_[Pointer::POINTER_SPRING];
+    delete pointer_[Pointer::POINTER_WIGGLY];
+    delete pointer_[Pointer::POINTER_METRONOME];
+}
diff --git a/src/MousePointer.h b/src/MousePointer.h
index 7bb00d1..121deca 100644
--- a/src/MousePointer.h
+++ b/src/MousePointer.h
@@ -128,6 +128,7 @@ class MousePointer
     MousePointer();
     MousePointer(MousePointer const& copy) = delete;
     MousePointer& operator=(MousePointer const& copy) = delete;
+    ~MousePointer();
 
 public:
     static MousePointer& manager ()
diff --git a/src/Scene.cpp b/src/Scene.cpp
index cdf432c..6b69be8 100644
--- a/src/Scene.cpp
+++ b/src/Scene.cpp
@@ -224,18 +224,28 @@ void Primitive::accept(Visitor& v)
 
 void Primitive::replaceShader( Shader *newshader )
 {
-    if (newshader) {
+    // keep ref to previous shader
+    Shader *previousshader = shader_;
+
+    // apply new shader to Primitive, even if nullptr
+    shader_ = newshader;
+
+    if (shader_) {
+        // get new attribs...
         glm::mat4 iTransform = newshader->iTransform;
         glm::vec4 color = newshader->color;
-        if (shader_) {
-            iTransform = shader_->iTransform;
-            color = shader_->color;
-            delete shader_;
+        // ...or use previous shader attribs, if existed
+        if (previousshader) {
+            iTransform = previousshader->iTransform;
+            color = previousshader->color;
+            // shader is swapped, previous can be deleted
+            delete previousshader;
         }
+        // Apply attribs
         shader_->iTransform = iTransform;
         shader_->color = color;
     }
-    shader_ = newshader;
+
 }
 
 //
diff --git a/src/Settings.cpp b/src/Settings.cpp
index f2d10c0..978b3d4 100644
--- a/src/Settings.cpp
+++ b/src/Settings.cpp
@@ -423,7 +423,7 @@ void Settings::Load(const string &filename)
         return;
 
     // version
-    int major, minor, patch;
+    int major = 0, minor = 0, patch = 0;
     pRoot->QueryIntAttribute("major", &major);
     pRoot->QueryIntAttribute("minor", &minor);
     pRoot->QueryIntAttribute("patch", &patch);
diff --git a/src/Stream.cpp b/src/Stream.cpp
index 3903389..db81cc3 100644
--- a/src/Stream.cpp
+++ b/src/Stream.cpp
@@ -382,8 +382,10 @@ void Stream::Frame::unmap()
 void Stream::pipeline_terminate( GstElement *p )
 {
 #ifdef STREAM_DEBUG
-    g_printerr("Stream %s close\n", gst_element_get_name(p));
-    Log::Info("Stream %s closed", gst_element_get_name(p));
+    gchar *name = gst_element_get_name(p);
+    g_printerr("Stream %s close\n", name);
+    Log::Info("Stream %s closed", name);
+    g_free(name);
 #endif
 
     // force flush