diff --git a/utsCharCache.pas b/utsCharCache.pas
index 542f116..9e12d76 100644
--- a/utsCharCache.pas
+++ b/utsCharCache.pas
@@ -73,7 +73,7 @@ type
     function GetChars(const aKey: TtsFont): TtsChars;
     function Find(const aMin, aMax: Integer; const aKey: TtsFont; out aIndex: Integer): Integer;
   protected
-    procedure DelSlave(const aSlave: TtsRefManager); override;
+    function DelSlave(const aSlave: TtsRefManager): Boolean; override;
   public
     property Chars[const aKey: TtsFont]: TtsChars read GetChars;
 
@@ -459,19 +459,22 @@ begin
 end;
 
 ////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
-procedure TtsCharCache.DelSlave(const aSlave: TtsRefManager);
+function TtsCharCache.DelSlave(const aSlave: TtsRefManager): Boolean;
 var
+  f: TtsFont;
   pos, index: Integer;
   p: PtsCharCacheItem;
 begin
-  pos := Find(0, fItems.Count-1, aSlave as TtsFont, index);
+  f := (aSlave as TtsFont);
+  f.DelMaster(self);
+  pos := Find(0, fItems.Count-1, f, index);
   if (pos >= 0) then begin
     p := PtsCharCacheItem(fItems[pos]);
     fItems.Delete(pos);
     FreeAndNil(p^.val);
     Dispose(p);
   end;
-  inherited DelSlave(aSlave);
+  result := inherited DelSlave(aSlave);
 end;
 
 ////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
@@ -482,10 +485,8 @@ var
 begin
   for i := 0 to fItems.Count-1 do begin
     p := PtsCharCacheItem(fItems[i]);
-    FreeAndNil(p^.val);
-    Dispose(p);
+    p^.key.DelMaster(self);
   end;
-  fItems.Clear;
 end;
 
 ////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
diff --git a/utsFont.pas b/utsFont.pas
index 213b656..8d9748a 100644
--- a/utsFont.pas
+++ b/utsFont.pas
@@ -22,7 +22,7 @@ type
     fCharSpacing: Integer;
     fLineSpacing: Single;
   protected
-    {%H-}constructor Create(const aMaster: TtsRefManager; const aMetric: TtsFontMetric; const aNames: TtsFontNames);
+    {%H-}constructor Create(const aCreator: TtsRefManager; const aMetric: TtsFontMetric; const aNames: TtsFontNames);
   public
     property Names:         TtsFontNames     read fNames;
     property Metric:        TtsFontMetric    read fMetric;
@@ -42,9 +42,9 @@ implementation
 ///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
 //TtsFont//////////////////////////////////////////////////////////////////////////////////////////////////////////////
 ////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
-constructor TtsFont.Create(const aMaster: TtsRefManager; const aMetric: TtsFontMetric; const aNames: TtsFontNames);
+constructor TtsFont.Create(const aCreator: TtsRefManager; const aMetric: TtsFontMetric; const aNames: TtsFontNames);
 begin
-  inherited Create(aMaster);
+  inherited Create(aCreator);
   fMetric := aMetric;
   fNames  := aNames;
 end;
diff --git a/utsOpenGLUtils.pas b/utsOpenGLUtils.pas
index cd01c09..f3ac084 100644
--- a/utsOpenGLUtils.pas
+++ b/utsOpenGLUtils.pas
@@ -149,6 +149,10 @@ begin
   if Assigned(aTexture^.Next) then
     aTexture^.Next^.Prev := aTexture^.Prev;
   Dispose(aTexture);
+  if (fFirstTexture = aTexture) then begin
+    fFirstTexture := nil;
+    fLastTexture  := nil;
+  end;
   aTexture := nil;
 end;
 
@@ -325,18 +329,14 @@ begin
       if (tex^.ID = ref.TextureID) then begin
         if not RemoveFromTree(tex^.Usage, 0, 0, tex^.Size, tex^.Size) then
           raise EtsRendererOpenGL.Create('unable to remove render ref from texture');
-        if IsEmtpy(tex^.Usage) then begin
-          if (tex = fFirstTexture) then
-            fFirstTexture := nil;
+        if IsEmtpy(tex^.Usage) then
           FreeTexture(tex);
-        end;
         tex := nil;
       end else
         tex := tex^.Next;
     end;
   finally
-    if Assigned(ref) then
-      ref.Free;
+    FreeAndNil(ref);
   end;
 end;
 
diff --git a/utsUtils.pas b/utsUtils.pas
index 8594c9a..56d527c 100644
--- a/utsUtils.pas
+++ b/utsUtils.pas
@@ -14,11 +14,11 @@ type
 ////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
   TtsRefManager = class(TObject)
   private
-    fMasterRef: TtsRefManager;
-    fSlaveRefs: TObjectList;
+    fMasterRef: TtsRefManager;  // master of this object (master will destroy this object)
+    fSlaveRefs: TObjectList;    // slaves of this object (will destroy all slaves when this objects is destroyed)
   protected
     procedure AddSlave(const aSlave: TtsRefManager); virtual;
-    procedure DelSlave(const aSlave: TtsRefManager); virtual;
+    function DelSlave(const aSlave: TtsRefManager): Boolean; virtual;
   public
     constructor Create(const aMaster: TtsRefManager);
     destructor Destroy; override;
@@ -126,10 +126,11 @@ begin
 end;
 
 ////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
-procedure TtsRefManager.DelSlave(const aSlave: TtsRefManager);
+function TtsRefManager.DelSlave(const aSlave: TtsRefManager): Boolean;
 begin
+  result := false;
   if Assigned(fSlaveRefs) then
-    fSlaveRefs.Remove(aSlave);
+    result := (fSlaveRefs.Remove(aSlave) >= 0);
 end;
 
 ////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////