diff --git a/firmware/target/arm/as3525/system-as3525.c b/firmware/target/arm/as3525/system-as3525.c
index 47cb465..a837f7f 100644
--- a/firmware/target/arm/as3525/system-as3525.c
+++ b/firmware/target/arm/as3525/system-as3525.c
@@ -294,6 +294,8 @@ void system_init(void)
         & ~CCU_SRC_IDE_EN; /* FIXME */
 #endif
 
+    MPMC_DYNAMIC_CONTROL = 0x0; /* MPMCCLKOUT stops when all SDRAMs are idle */
+
     unsigned int reset_loops = 640;
     while(reset_loops--)
         CCU_SRL = CCU_SRL_MAGIC_NUMBER;