diff --git a/armsrc/iclass.c b/armsrc/iclass.c
index 329e17655..72cfbefc3 100644
--- a/armsrc/iclass.c
+++ b/armsrc/iclass.c
@@ -998,7 +998,7 @@ void SimulateIClass(uint32_t arg0, uint32_t arg1, uint32_t arg2, uint8_t *datain
 	else if(simType == 2)
 	{
 
-		uint8_t mac_responses[64] = { 0 };
+		uint8_t mac_responses[USB_CMD_DATA_SIZE] = { 0 };
 		Dbprintf("Going into attack mode, %d CSNS sent", numberOfCSNS);
 		// In this mode, a number of csns are within datain. We'll simulate each one, one at a time
 		// in order to collect MAC's from the reader. This can later be used in an offlne-attack
@@ -1248,6 +1248,8 @@ int doIClassSimulation(uint8_t csn[], int breakAfterMacReceived, uint8_t *reader
 	//Dbprintf("%x", cmdsRecvd);
 	LED_A_OFF();
 	LED_B_OFF();
+	LED_C_OFF();
+
 	if(buttonPressed)
 	{
 		DbpString("Button pressed");