diff --git a/src/fader.c b/src/fader.c
index 4f63f33..8de1791 100644
--- a/src/fader.c
+++ b/src/fader.c
@@ -11,6 +11,8 @@ uint8_t numModules;
 float fadestep = 1;
 double nextFrame;
 
+int somethingChanged = 0; // indicates when a ws2801 update is required
+
 static const double interval = 0.01f;
 
 struct Colour {
@@ -59,6 +61,8 @@ void fader_set_colour(uint8_t module, uint8_t r, uint8_t g, uint8_t b)
 	curColour[module].red   = targetColour[module].red   = r;
 	curColour[module].green = targetColour[module].green = g;
 	curColour[module].blue  = targetColour[module].blue  = b;
+
+	somethingChanged = 1;
 }
 
 void fader_fade_colour(uint8_t module, uint8_t r, uint8_t g, uint8_t b)
@@ -85,6 +89,8 @@ void fader_add_colour(uint8_t module, uint8_t r, uint8_t g, uint8_t b)
 	if(targetColour[module].red > 255) { targetColour[module].red = 255; }
 	if(targetColour[module].green > 255) { targetColour[module].green = 255; }
 	if(targetColour[module].blue > 255) { targetColour[module].blue = 255; }
+
+	somethingChanged = 1;
 }
 
 void fader_set_fadestep(uint8_t newFadestep)
@@ -94,7 +100,14 @@ void fader_set_fadestep(uint8_t newFadestep)
 	fadestep = (float)newFadestep * interval / 0.04f;
 }
 
-void fade_colour(float *cur, const float *target)
+/*!
+ * Fade the colour value in cur towards target.
+ *
+ * \param cur      The colour value to update.
+ * \param target   The target value that should be reached.
+ * \param changed  Output value which is set to 1 if cur was changed.
+ */
+void fade_colour(float *cur, const float *target, int *changed)
 {
 	float diff;
 	if(*cur > *target) {
@@ -104,6 +117,8 @@ void fade_colour(float *cur, const float *target)
 		} else {
 			*cur -= fadestep;
 		}
+
+		*changed = 1;
 	} else if(*cur < *target) {
 		diff = *target - *cur;
 		if(diff < fadestep) {
@@ -111,15 +126,17 @@ void fade_colour(float *cur, const float *target)
 		} else {
 			*cur += fadestep;
 		}
+
+		*changed = 1;
 	}
 }
 
 void fader_update(void)
 {
 	for(uint8_t i = 0; i < numModules; i++) {
-		fade_colour(&(curColour[i].red), &(targetColour[i].red));
-		fade_colour(&(curColour[i].green), &(targetColour[i].green));
-		fade_colour(&(curColour[i].blue), &(targetColour[i].blue));
+		fade_colour(&(curColour[i].red), &(targetColour[i].red), &somethingChanged);
+		fade_colour(&(curColour[i].green), &(targetColour[i].green), &somethingChanged);
+		fade_colour(&(curColour[i].blue), &(targetColour[i].blue), &somethingChanged);
 
 		ws2801_set_colour(i,
 				(uint8_t)curColour[i].red,
@@ -127,7 +144,10 @@ void fader_update(void)
 				(uint8_t)curColour[i].blue);
 	}
 
-	ws2801_send_update();
+	if(somethingChanged) {
+		ws2801_send_update();
+		somethingChanged = 0;
+	}
 }
 
 void fader_wait_frame(void)