diff --git a/targets/ARCH/rfsimulator/simulator.c b/targets/ARCH/rfsimulator/simulator.c
index 79bf3dd077..b469211a35 100644
--- a/targets/ARCH/rfsimulator/simulator.c
+++ b/targets/ARCH/rfsimulator/simulator.c
@@ -54,7 +54,7 @@
 #include <targets/ARCH/rfsimulator/rfsimulator.h>
 
 #define PORT 4043 //default TCP port for this simulator
-#define CirSize 307200 // 100ms is enough
+#define CirSize 6144000 // 100ms is enough
 #define sampleToByte(a,b) ((a)*(b)*sizeof(sample_t))
 #define byteToSample(a,b) ((a)/(sizeof(sample_t)*(b)))