diff --git a/firmware/backlight.c b/firmware/backlight.c
index 25a91632cd..5e79e4e479 100644
--- a/firmware/backlight.c
+++ b/firmware/backlight.c
@@ -547,13 +547,29 @@ void remote_backlight_set_timeout(int index) {(void)index;}
 #endif /* #ifdef CONFIG_BACKLIGHT */
 
 #ifdef HAVE_BACKLIGHT_BRIGHTNESS
+#ifdef IRIVER_H300_SERIES
 void backlight_set_brightness(int val)
 {
     /* set H300 brightness by changing the PWM
-       accepts 0..15 but note that 0 and 1 gives a black display! */
-    if(val < MIN_BRIGHTNESS_SETTING)
-            val = MIN_BRIGHTNESS_SETTING;
-    pcf50606_set_bl_pwm(val & 0xf);
+       accepts 0..15 but note that 0 and 1 give a black display! */
+    val &= 0x0F;
+    if(val<MIN_BRIGHTNESS_SETTING)
+        val=MIN_BRIGHTNESS_SETTING;
+
+    /* shift one bit left */
+    val <<= 1;
+
+    /* enable PWM */
+    val |= 0x01;
+
+    /* disable IRQs while bitbanging */
+    int old_irq_level = set_irq_level(HIGHEST_IRQ_LEVEL);
+
+    pcf50606_write(0x35, val);
+
+    /* enable IRQs again */
+    set_irq_level(old_irq_level);
 }
 #endif
+#endif
 
diff --git a/firmware/drivers/pcf50606.c b/firmware/drivers/pcf50606.c
index af2c2ca2eb..f4c93deb38 100644
--- a/firmware/drivers/pcf50606.c
+++ b/firmware/drivers/pcf50606.c
@@ -44,8 +44,6 @@
 /* delay loop to achieve 400kHz at 120MHz CPU frequency */
 #define DELAY    do { int _x; for(_x=0;_x<22;_x++);} while(0)
 
-void pcf50606_set_bl_pwm(unsigned char ucVal);
-
 static void pcf50606_i2c_start(void)
 {
     SDA_OUTPUT;
@@ -285,24 +283,5 @@ void pcf50606_init(void)
     pcf50606_write(0x09, 0x05); /* USB and ON key debounce: 14ms */
     pcf50606_write(0x29, 0x1C); /* Disable the unused MBC module */
     
-     /* Backlight PWM = 512Hz 50/50 */
-    /*pcf50606_write(0x35, 0x13);*/
-    pcf50606_set_bl_pwm(9);
-}
-
-void pcf50606_set_bl_pwm(unsigned char ucVal)
-{
-    /* set the backlight PWM */
-    /* range is 0 - 15 */
-
-    /* limit incoming value */
-    ucVal = ucVal & 0x0F;   
-
-    /* shift one bit left */
-    ucVal = ucVal << 1;
-    ucVal = ucVal | 0x01;
-
-    /* 0x00 = 512Hz */
-    ucVal = ucVal | 0x00;   
-    pcf50606_write(0x35, ucVal);
+    pcf50606_write(0x35, 0x13); /* Backlight PWM = 512Hz 50/50 */
 }
diff --git a/firmware/export/pcf50606.h b/firmware/export/pcf50606.h
index daacbac725..fd180bfaee 100644
--- a/firmware/export/pcf50606.h
+++ b/firmware/export/pcf50606.h
@@ -25,7 +25,6 @@ int pcf50606_write_multiple(int address, const unsigned char* buf, int count);
 int pcf50606_write(int address, unsigned char val);
 int pcf50606_read_multiple(int address, unsigned char* buf, int count);
 int pcf50606_read(int address);
-void pcf50606_set_bl_pwm(unsigned char ucVal);
 #endif
 
 #endif