diff --git a/modules/gui/macosx/VLCDefaultValueSlider.m b/modules/gui/macosx/VLCDefaultValueSlider.m
index 16e689a46721f644be2be2c05531a982daee75ca..8e6ae1c7a912f926786b9e31c1df1fc80113b18a 100644
--- a/modules/gui/macosx/VLCDefaultValueSlider.m
+++ b/modules/gui/macosx/VLCDefaultValueSlider.m
@@ -30,9 +30,8 @@
 {
     self = [super initWithCoder:coder];
     if (self) {
-        if (![self.cell isKindOfClass:[VLCDefaultValueSliderCell class]]) {
-            self.cell = [[VLCDefaultValueSliderCell alloc] init];
-        }
+        NSAssert([self.cell isKindOfClass:[VLCDefaultValueSliderCell class]],
+                 @"VLCDefaultSlider cell is not VLCDefaultValueSliderCell");
         _isScrollable = YES;
     }
     return self;
diff --git a/modules/gui/macosx/VLCSlider.m b/modules/gui/macosx/VLCSlider.m
index 787721ecf3d060cb690496399a08ae4d966816ff..245c4faab07a6ceeb95a272ff3beeae73287f58b 100644
--- a/modules/gui/macosx/VLCSlider.m
+++ b/modules/gui/macosx/VLCSlider.m
@@ -31,9 +31,8 @@
     self = [super initWithCoder:coder];
 
     if (self) {
-        if (![self.cell isKindOfClass:[VLCSliderCell class]]) {
-            self.cell = [[VLCSliderCell alloc] init];
-        }
+        NSAssert([self.cell isKindOfClass:[VLCSliderCell class]],
+                 @"VLCSlider cell is not VLCSliderCell");
     }
     return self;
 }
@@ -49,14 +48,6 @@
     [super setNeedsDisplayInRect:[self bounds]];
 }
 
-- (void)awakeFromNib {
-    [super awakeFromNib];
-
-    if(![self.cell isKindOfClass:[VLCSliderCell class]]) {
-        self.cell = [[VLCSliderCell alloc] init];
-    }
-}
-
 - (BOOL)getIndefinite
 {
     return [(VLCSliderCell*)[self cell] indefinite];
diff --git a/modules/gui/macosx/VLCVolumeSlider.m b/modules/gui/macosx/VLCVolumeSlider.m
index 300dbdf54512a122156249e81d5886816b0d4adb..b912f9c7c4434a399bfde01a3b0ceb3e03f1efaf 100644
--- a/modules/gui/macosx/VLCVolumeSlider.m
+++ b/modules/gui/macosx/VLCVolumeSlider.m
@@ -32,9 +32,8 @@
     self = [super initWithCoder:coder];
 
     if (self) {
-        if (![self.cell isKindOfClass:[VLCVolumeSliderCell class]]) {
-            self.cell = [[VLCVolumeSliderCell alloc] init];
-        }
+        NSAssert([self.cell isKindOfClass:[VLCVolumeSliderCell class]],
+                 @"VLCVolumeSlider cell is not VLCVolumeSliderCell");
     }
     return self;
 }