diff --git a/firmware/export/config/sansaclipplus.h b/firmware/export/config/sansaclipplus.h
index ab4408a..12151a7 100644
--- a/firmware/export/config/sansaclipplus.h
+++ b/firmware/export/config/sansaclipplus.h
@@ -188,7 +188,7 @@
 #define CONFIG_LED LED_VIRTUAL
 
 /* Define this if you have adjustable CPU frequency */
-//#define HAVE_ADJUSTABLE_CPU_FREQ
+#define HAVE_ADJUSTABLE_CPU_FREQ
 
 #define BOOTFILE_EXT    "sansa"
 #define BOOTFILE        "rockbox." BOOTFILE_EXT
diff --git a/firmware/export/config/sansaclipv2.h b/firmware/export/config/sansaclipv2.h
index 262ed36..4b83b32 100644
--- a/firmware/export/config/sansaclipv2.h
+++ b/firmware/export/config/sansaclipv2.h
@@ -181,7 +181,7 @@
 #define CONFIG_LED LED_VIRTUAL
 
 /* Define this if you have adjustable CPU frequency */
-//#define HAVE_ADJUSTABLE_CPU_FREQ
+#define HAVE_ADJUSTABLE_CPU_FREQ
 
 #define BOOTFILE_EXT    "sansa"
 #define BOOTFILE        "rockbox." BOOTFILE_EXT
diff --git a/firmware/target/arm/as3525/system-as3525.c b/firmware/target/arm/as3525/system-as3525.c
index 44e210a..8b09872 100644
--- a/firmware/target/arm/as3525/system-as3525.c
+++ b/firmware/target/arm/as3525/system-as3525.c
@@ -459,8 +459,6 @@ void set_cpu_frequency(long frequency)
     }
 }
 #else   /* as3525v2  */
-/* FIXME : disabled for now, seems to cause buggy memory accesses
- * Disabling MMU or putting the function in uncached memory seems to help? */
 void set_cpu_frequency(long frequency)
 {
     int oldstatus = disable_irq_save();
@@ -470,21 +468,52 @@ void set_cpu_frequency(long frequency)
 
     if(frequency == CPUFREQ_MAX)
     {
-        /* Change PCLK while FCLK is low, so it doesn't go too high */
-        CGU_PERI = (CGU_PERI & ~(0xF << 2)) | (AS3525_PCLK_DIV0 << 2);
-
-        CGU_PROC = ((AS3525_FCLK_POSTDIV << 4) |
-                    (AS3525_FCLK_PREDIV  << 2) |
-                    AS3525_FCLK_SEL);
+        /* Clip: fclk 24MHz -> 240MHz */
+        static const uint8_t div[][2] = {
+        /* -> change fclk -> tmp pclk -> change pclk -> new pclk */
+        /* fclk div  pclk  div         fclk     tmp pclk      new pclk */
+            { 10,       1 },    //      24          24          24
+            { 5 ,       2 },    //      48          48          24
+            { 3 ,       3 },    //      80          40          26.66
+            { 2 ,       5 },    //      120         40          24
+            { 1,       10 },    //      240         48          24
+        };
+
+        const size_t max = sizeof(div)/sizeof(div[0]);
+        unsigned i = 1; /* skip 1st entry */
+        for(; i<max; i++)
+        {
+            CGU_PROC = (((div[i][0] - 1)<< 4) |
+                        (AS3525_FCLK_PREDIV  << 2) |
+                        AS3525_FCLK_SEL);
+
+            CGU_PERI = (CGU_PERI & ~(0xF << 2)) | ((div[i][1] - 1)<< 2);
+
+        }
     }
     else
     {
-        CGU_PROC = ((AS3525_FCLK_POSTDIV_UNBOOSTED << 4) |
-                    (AS3525_FCLK_PREDIV  << 2) |
-                    AS3525_FCLK_SEL);
-
-        /* Change PCLK after FCLK is low, so it doesn't go too high */
-        CGU_PERI = (CGU_PERI & ~(0xF << 2)) | (AS3525_PCLK_DIV0_UNBOOSTED << 2);
+        /* Clip: fclk 240MHz -> 24MHz */
+        static const uint8_t div[][2] = {
+        /* -> change fclk -> tmp pclk -> change pclk -> new pclk */
+        /* fclk div  pclk  div         fclk     tmp pclk      new pclk */
+            { 1,       10 },    //      240         24          24
+            { 2 ,       5 },    //      120         48          24
+            { 3 ,       2 },    //      80          20          40
+            { 5 ,       1 },    //      48          24          48
+            { 10,       1 },    //      24          24          24
+        };
+
+        const size_t max = sizeof(div)/sizeof(div[0]);
+        unsigned i = 1; /* skip 1st entry */
+        for(; i<max; i++)
+        {
+            CGU_PROC = (((div[i][0] - 1)<< 4) |
+                        (AS3525_FCLK_PREDIV  << 2) |
+                        AS3525_FCLK_SEL);
+
+            CGU_PERI = (CGU_PERI & ~(0xF << 2)) | ((div[i][1] - 1)<< 2);
+        }
     }
 
     restore_irq(oldstatus);