diff --git a/PartyModes/PartyModeChallengeMedley/CChallengeRounds.cs b/PartyModes/PartyModeChallengeMedley/CChallengeRounds.cs
index ea149cdc..7b6310c1 100644
--- a/PartyModes/PartyModeChallengeMedley/CChallengeRounds.cs
+++ b/PartyModes/PartyModeChallengeMedley/CChallengeRounds.cs
@@ -237,7 +237,7 @@ namespace VocaluxeLib.PartyModes.ChallengeMedley
             return false;
         }
 
-        public bool IsAvailableAll(List<int> playerIndices)
+        public bool IsAvailableAll(IEnumerable<int> playerIndices)
         {
             bool result = true;
             foreach (int p in playerIndices)
@@ -245,7 +245,7 @@ namespace VocaluxeLib.PartyModes.ChallengeMedley
             return result;
         }
 
-        public bool IsAvailableSomeone(List<int> playerIndices)
+        public bool IsAvailableSomeone(IEnumerable<int> playerIndices)
         {
             bool result = false;
             foreach (int p in playerIndices)
diff --git a/Vocaluxe/Base/CDataBase.cs b/Vocaluxe/Base/CDataBase.cs
index b130d5e4..d44dce78 100644
--- a/Vocaluxe/Base/CDataBase.cs
+++ b/Vocaluxe/Base/CDataBase.cs
@@ -1415,10 +1415,10 @@ namespace Vocaluxe.Base
         {
             const int chunkSize = 2 * 1024;
             byte[] buffer = new byte[chunkSize];
-            long bytesRead;
             long fieldOffset = 0;
             using (MemoryStream stream = new MemoryStream())
             {
+                long bytesRead;
                 while ((bytesRead = reader.GetBytes(0, fieldOffset, buffer, 0, buffer.Length)) > 0)
                 {
                     byte[] actualRead = new byte[bytesRead];
diff --git a/Vocaluxe/Base/CGraphics.cs b/Vocaluxe/Base/CGraphics.cs
index 5f9f3078..eff9e0c4 100644
--- a/Vocaluxe/Base/CGraphics.cs
+++ b/Vocaluxe/Base/CGraphics.cs
@@ -794,8 +794,7 @@ namespace Vocaluxe.Base
 
             if (CTheme.Cursor.Color != "")
             {
-                SColorF color;
-                color = CTheme.GetColor(CTheme.Cursor.Color, -1);
+                SColorF color = CTheme.GetColor(CTheme.Cursor.Color, -1);
                 CTheme.Cursor.R = color.R;
                 CTheme.Cursor.G = color.G;
                 CTheme.Cursor.B = color.B;
diff --git a/Vocaluxe/Base/CLanguage.cs b/Vocaluxe/Base/CLanguage.cs
index 00b2d6e5..c9024d67 100644
--- a/Vocaluxe/Base/CLanguage.cs
+++ b/Vocaluxe/Base/CLanguage.cs
@@ -63,7 +63,7 @@ namespace Vocaluxe.Base
             return _Languages[lang].Name;
         }
 
-        public static string[] GetLanguageNames()
+        public static IEnumerable<string> GetLanguageNames()
         {
             string[] languages = new string[_Languages.Count];
 
@@ -179,7 +179,7 @@ namespace Vocaluxe.Base
         private static bool _LoadLanguageEntries(CXMLReader xmlReader, out Dictionary<string, string> texts)
         {
             texts = new Dictionary<string, string>();
-            List<string> names = xmlReader.GetAttributes("resources", "name");
+            IEnumerable<string> names = xmlReader.GetAttributes("resources", "name");
             foreach (string name in names)
             {
                 string value;
diff --git a/Vocaluxe/Base/CMain.cs b/Vocaluxe/Base/CMain.cs
index 0b77a945..64cbbb9c 100644
--- a/Vocaluxe/Base/CMain.cs
+++ b/Vocaluxe/Base/CMain.cs
@@ -27,11 +27,11 @@ namespace Vocaluxe.Base
 {
     static class CMain
     {
-        public static IConfig Config = new CBconfig();
-        public static ISettings Settings = new CBsettings();
-        public static ITheme Theme = new CBtheme();
-        public static IBackgroundMusic BackgroundMusic = new CBbackgroundMusic();
-        public static IDrawing Draw = new CBdraw();
+        public static readonly IConfig Config = new CBconfig();
+        public static readonly ISettings Settings = new CBsettings();
+        public static readonly ITheme Theme = new CBtheme();
+        public static readonly IBackgroundMusic BackgroundMusic = new CBbackgroundMusic();
+        public static readonly IDrawing Draw = new CBdraw();
         public static IGraphics Graphics = new CBGraphics();
         public static ILog Log = new CBlog();
         public static IFonts Fonts = new CBfonts();
@@ -113,7 +113,7 @@ namespace Vocaluxe.Base
             return CConfig.CoverSize;
         }
 
-        public List<string> GetSongFolder()
+        public IEnumerable<string> GetSongFolder()
         {
             return CConfig.SongFolder;
         }
diff --git a/Vocaluxe/Base/CPlaylists.cs b/Vocaluxe/Base/CPlaylists.cs
index 9fad3f43..d71bcda5 100644
--- a/Vocaluxe/Base/CPlaylists.cs
+++ b/Vocaluxe/Base/CPlaylists.cs
@@ -36,7 +36,7 @@ namespace Vocaluxe.Base
             get { return _Playlists.ToArray(); }
         }
 
-        public static string[] PlaylistNames
+        public static IEnumerable<string> PlaylistNames
         {
             get
             {
@@ -227,7 +227,7 @@ namespace Vocaluxe.Base
 
         private static int _CompareByPlaylistName(CPlaylistFile a, CPlaylistFile b)
         {
-            return String.Compare(a.PlaylistName, b.PlaylistName);
+            return System.String.CompareOrdinal(a.PlaylistName, b.PlaylistName);
         }
 
         private static CPlaylistFile _ConvertUSDXPlaylist(string file)
@@ -237,9 +237,9 @@ namespace Vocaluxe.Base
 
             if (!File.Exists(file))
                 return null;
-            StreamReader sr;
             try
             {
+                StreamReader sr;
                 using (sr = new StreamReader(file, Encoding.Default, true))
                 {
                     string line;
diff --git a/Vocaluxe/Base/CProfiles.cs b/Vocaluxe/Base/CProfiles.cs
index 76e910d8..d69effda 100644
--- a/Vocaluxe/Base/CProfiles.cs
+++ b/Vocaluxe/Base/CProfiles.cs
@@ -282,7 +282,7 @@ namespace Vocaluxe.Base
 
         private static int _CompareByPlayerName(SProfile a, SProfile b)
         {
-            return String.Compare(a.PlayerName, b.PlayerName);
+            return System.String.CompareOrdinal(a.PlayerName, b.PlayerName);
         }
 
         #region private methods
diff --git a/Vocaluxe/Lib/Sound/CDirectSoundRecord.cs b/Vocaluxe/Lib/Sound/CDirectSoundRecord.cs
index a26c9003..746e4bca 100644
--- a/Vocaluxe/Lib/Sound/CDirectSoundRecord.cs
+++ b/Vocaluxe/Lib/Sound/CDirectSoundRecord.cs
@@ -383,13 +383,12 @@ namespace Vocaluxe.Lib.Sound
 
                 // Buffer type must match this.waveFormat.FormatTag and this.waveFormat.BitsPerSample
                 byte[] bufferPortion = new byte[bufferPortionSamples];
-                int bufferPortionIndex;
 
                 _CaptureBuffer.Start(true);
 
                 while (_Running)
                 {
-                    bufferPortionIndex = WaitHandle.WaitAny(_WaitHandles);
+                    int bufferPortionIndex = WaitHandle.WaitAny(_WaitHandles);
 
                     _CaptureBuffer.Read(
                         bufferPortion,
diff --git a/Vocaluxe/Screens/CScreenCredits.cs b/Vocaluxe/Screens/CScreenCredits.cs
index c9df9ec0..d8a17f78 100644
--- a/Vocaluxe/Screens/CScreenCredits.cs
+++ b/Vocaluxe/Screens/CScreenCredits.cs
@@ -152,13 +152,10 @@ namespace Vocaluxe.Screens
             _ParagraphTexts = new List<CText>();
             _Paragraphs = new List<string[]>();
 
-            string paragraph;
-            string[] words;
-
-            paragraph = "Inspired by the achievements of UltraStar Deluxe and its variants and pursuing the goal of making " +
-                        "a good thing even better, we ended up rewriting the game from scratch. And a new implementation in a new " +
-                        "programming language called for a new name - and VOCALUXE [ˈvoʊˈkəˈlʌks] it is!";
-            words = paragraph.Split(new char[] {' '});
+            string paragraph = "Inspired by the achievements of UltraStar Deluxe and its variants and pursuing the goal of making " +
+                               "a good thing even better, we ended up rewriting the game from scratch. And a new implementation in a new " +
+                               "programming language called for a new name - and VOCALUXE [ˈvoʊˈkəˈlʌks] it is!";
+            string[] words = paragraph.Split(new char[] {' '});
             _Paragraphs.Add(words);
 
             paragraph = "This first public version has already implemented many of the original features and it is fully " +
diff --git a/Vocaluxe/Screens/CScreenSong.cs b/Vocaluxe/Screens/CScreenSong.cs
index 6108ade4..85551067 100644
--- a/Vocaluxe/Screens/CScreenSong.cs
+++ b/Vocaluxe/Screens/CScreenSong.cs
@@ -819,8 +819,7 @@ namespace Vocaluxe.Screens
         {
             if (CSongs.Category >= 0 && songNr >= 0 && CSongs.NumVisibleSongs > songNr)
             {
-                EGameMode gm;
-                gm = CSongs.VisibleSongs[songNr].IsDuet ? EGameMode.TR_GAMEMODE_DUET : EGameMode.TR_GAMEMODE_NORMAL;
+                EGameMode gm = CSongs.VisibleSongs[songNr].IsDuet ? EGameMode.TR_GAMEMODE_DUET : EGameMode.TR_GAMEMODE_NORMAL;
 
                 CGame.Reset();
                 CGame.ClearSongs();
diff --git a/VocaluxeLib/Menu/CMenuParty.cs b/VocaluxeLib/Menu/CMenuParty.cs
index 2cd1fa5c..965f6175 100644
--- a/VocaluxeLib/Menu/CMenuParty.cs
+++ b/VocaluxeLib/Menu/CMenuParty.cs
@@ -26,7 +26,7 @@ namespace VocaluxeLib.Menu
     {
         protected IPartyMode _PartyMode;
 
-        public CMenuParty()
+        protected CMenuParty()
         {
             _PartyMode = new CPartyModeNone();
         }
diff --git a/VocaluxeLib/Menu/CSelectSlide.cs b/VocaluxeLib/Menu/CSelectSlide.cs
index a79d9e93..66ad5b95 100644
--- a/VocaluxeLib/Menu/CSelectSlide.cs
+++ b/VocaluxeLib/Menu/CSelectSlide.cs
@@ -556,7 +556,7 @@ namespace VocaluxeLib.Menu
             _ValueBounds.Clear();
         }
 
-        public void AddValues(string[] values)
+        public void AddValues(IEnumerable<string> values)
         {
             foreach (string value in values)
                 _AddValue(value, new STexture(-1), _PartyModeID);
diff --git a/VocaluxeLib/Menu/CXMLReader.cs b/VocaluxeLib/Menu/CXMLReader.cs
index 55944771..6173699b 100644
--- a/VocaluxeLib/Menu/CXMLReader.cs
+++ b/VocaluxeLib/Menu/CXMLReader.cs
@@ -141,7 +141,7 @@ namespace VocaluxeLib.Menu
             return values;
         }
 
-        public List<string> GetAttributes(string cast, string attribute)
+        public IEnumerable<string> GetAttributes(string cast, string attribute)
         {
             List<string> values = new List<string>();
 
@@ -180,11 +180,10 @@ namespace VocaluxeLib.Menu
 
         public bool ItemExists(string cast)
         {
-            XPathNodeIterator iterator;
             int results = 0;
 
             _Navigator.MoveToFirstChild();
-            iterator = _Navigator.Select(cast);
+            XPathNodeIterator iterator = _Navigator.Select(cast);
 
             while (iterator.MoveNext())
                 results++;
diff --git a/VocaluxeLib/Menu/IMenu.cs b/VocaluxeLib/Menu/IMenu.cs
index 70813cfc..28b278f7 100644
--- a/VocaluxeLib/Menu/IMenu.cs
+++ b/VocaluxeLib/Menu/IMenu.cs
@@ -86,7 +86,7 @@ namespace VocaluxeLib.Menu
 
         int GetCoverSize();
 
-        List<string> GetSongFolder();
+        IEnumerable<string> GetSongFolder();
         ESongSorting GetSongSorting();
         EOffOn GetTabs();
         EOffOn GetIgnoreArticles();
diff --git a/VocaluxeLib/Menu/SingNotes/CNotes.cs b/VocaluxeLib/Menu/SingNotes/CNotes.cs
index 7c7413ba..1794834c 100644
--- a/VocaluxeLib/Menu/SingNotes/CNotes.cs
+++ b/VocaluxeLib/Menu/SingNotes/CNotes.cs
@@ -707,7 +707,6 @@ namespace VocaluxeLib.Menu.SingNotes
         public void UpdateTimings()
         {
             CNote lastNote;
-            int min, max, s;
 
             if (_Lines.Count > 0)
                 _Lines[0].StartBeat = -10000;
@@ -719,9 +718,10 @@ namespace VocaluxeLib.Menu.SingNotes
 
                 if ((lastNote != null) && (firstNote != null))
                 {
-                    min = lastNote.EndBeat;
-                    max = firstNote.StartBeat;
+                    int min = lastNote.EndBeat;
+                    int max = firstNote.StartBeat;
 
+                    int s;
                     switch (max - min)
                     {
                         case 0:
diff --git a/VocaluxeLib/Menu/SingNotes/CSingNotes.cs b/VocaluxeLib/Menu/SingNotes/CSingNotes.cs
index 9e254aee..06c227e8 100644
--- a/VocaluxeLib/Menu/SingNotes/CSingNotes.cs
+++ b/VocaluxeLib/Menu/SingNotes/CSingNotes.cs
@@ -74,7 +74,7 @@ namespace VocaluxeLib.Menu.SingNotes
         /// </remarks>
         public SRectF[,] BarPos { get; set; }
 
-        public CSingNotes(int partyModeID)
+        protected CSingNotes(int partyModeID)
         {
             _PartyModeID = partyModeID;
             _Theme = new SThemeSingBar();
diff --git a/VocaluxeLib/Menu/SongMenu/CSongMenuFramework.cs b/VocaluxeLib/Menu/SongMenu/CSongMenuFramework.cs
index 2fa3ed64..e4cc0766 100644
--- a/VocaluxeLib/Menu/SongMenu/CSongMenuFramework.cs
+++ b/VocaluxeLib/Menu/SongMenu/CSongMenuFramework.cs
@@ -234,7 +234,7 @@ namespace VocaluxeLib.Menu.SongMenu
             _Visible = visible;
         }
 
-        public CSongMenuFramework(int partyModeID)
+        protected CSongMenuFramework(int partyModeID)
         {
             _PartyModeID = partyModeID;
             _Theme = new SThemeSongMenu
diff --git a/VocaluxeLib/PartyModes/CPartyMode.cs b/VocaluxeLib/PartyModes/CPartyMode.cs
index de9c9b7a..cbc74a52 100644
--- a/VocaluxeLib/PartyModes/CPartyMode.cs
+++ b/VocaluxeLib/PartyModes/CPartyMode.cs
@@ -28,7 +28,7 @@ namespace VocaluxeLib.PartyModes
         protected SScreenSongOptions _ScreenSongOptions;
         protected readonly Dictionary<string, CMenuParty> _Screens;
 
-        public CPartyMode()
+        protected CPartyMode()
         {
             _Screens = new Dictionary<string, CMenuParty>();
             _ScreenSongOptions = new SScreenSongOptions {Selection = new SSelectionOptions(), Sorting = new SSortingOptions()};