diff --git a/Vocaluxe/Base/CBackgroundMusic.cs b/Vocaluxe/Base/CBackgroundMusic.cs
index 65165cf4..f9146f12 100644
--- a/Vocaluxe/Base/CBackgroundMusic.cs
+++ b/Vocaluxe/Base/CBackgroundMusic.cs
@@ -51,6 +51,7 @@ namespace Vocaluxe.Base
         private static Task _PreviewStartHelperTask;
         private static int _PreviewStartWaitCounter;
         private const int _PreviewStartWaitMaxTries = 10;
+        private static readonly object _PreviewStartHelperTaskLock = new Object();
 
         public static bool VideoEnabled
         {
@@ -256,10 +257,17 @@ namespace Vocaluxe.Base
         {
             if (_PreviewStartHelperTask != null && ( _PreviewPlayer.Length > 0 || _PreviewStartWaitCounter++ >= _PreviewStartWaitMaxTries))
             {
-                _PreviewStartHelperTask.RunSynchronously(TaskScheduler.FromCurrentSynchronizationContext());
-                _PreviewStartHelperTask.Dispose();
-                _PreviewStartHelperTask = null;
-                _PreviewStartWaitCounter = 0;
+                lock (_PreviewStartHelperTaskLock)
+                {
+                    // Recheck the condition as it cloud have change before we got the lock
+                    if (_PreviewStartHelperTask != null && (_PreviewPlayer.Length > 0 || _PreviewStartWaitCounter++ >= _PreviewStartWaitMaxTries))
+                    {
+                        _PreviewStartHelperTask.RunSynchronously(TaskScheduler.FromCurrentSynchronizationContext());
+                        _PreviewStartHelperTask.Dispose();
+                        _PreviewStartHelperTask = null;
+                        _PreviewStartWaitCounter = 0;
+                    }
+                }
             }
 
             if (!IsPlaying)
@@ -317,28 +325,46 @@ namespace Vocaluxe.Base
             //Change song position only if song is changed or near to end
             if (songChanged || _CurPlayer.Position + 30 < _CurPlayer.Length)
             {
-                _PreviewStartHelperTask = new Task(() =>
+                lock (_PreviewStartHelperTaskLock)
                 {
-                    float length = _PreviewPlayer.Length;
-                    if (length < 1)
-                        length = 30; // If length is unknow or invalid assume a length of 30s
+                    // Check if the old _PreviewStartHelperTask needs to disposed
+                    if (_PreviewStartHelperTask != null)
+                    {
+                        _PreviewStartHelperTask.Dispose();
+                    }
+                    _PreviewStartHelperTask = new Task(() =>
+                    {
+                        float length = _PreviewPlayer.Length;
+                        if (length < 1)
+                            length = 30; // If length is unknow or invalid assume a length of 30s
 
-                    if (start < 0)
-                        start = (song.Preview.Source == EDataSource.None) ? length / 4f : song.Preview.StartTime;
-                    if (start > length - 5f)
-                        start = Math.Max(0f, Math.Min(length / 4f, length - 5f));
-                    if (start >= 0.5f)
-                        start -= 0.5f;
+                        if (start < 0)
+                            start = (song.Preview.Source == EDataSource.None) ? length / 4f : song.Preview.StartTime;
+                        if (start > length - 5f)
+                            start = Math.Max(0f, Math.Min(length / 4f, length - 5f));
+                        if (start >= 0.5f)
+                            start -= 0.5f;
 
-                    _PreviewPlayer.Position = start;
-                    Play();
-                });
+                        _PreviewPlayer.Position = start;
+                        Play();
+                    });
+                }
                 _CurPlayer = _PreviewPlayer;
             }
             else
             {
-                _PreviewStartHelperTask.Dispose();
-                _PreviewStartHelperTask = null;
+                if (_PreviewStartHelperTask != null)
+                {
+                    lock (_PreviewStartHelperTaskLock)
+                    {
+                        // Recheck the condition as it cloud have change before we got the lock
+                        if (_PreviewStartHelperTask != null)
+                        {
+                            _PreviewStartHelperTask.Dispose();
+                            _PreviewStartHelperTask = null;
+                        }
+                    }
+                }
                 _PreviewPlayer.Position = _CurPlayer.Position;
                 _CurPlayer = _PreviewPlayer;
                 Play();