diff --git a/firmware/common/hackrf_core.c b/firmware/common/hackrf_core.c
index bb6ba3aa..d3329c6f 100644
--- a/firmware/common/hackrf_core.c
+++ b/firmware/common/hackrf_core.c
@@ -86,10 +86,16 @@ static struct gpio_t gpio_rffc5072_clock	= GPIO(5,  6);
 static struct gpio_t gpio_rffc5072_data		= GPIO(3,  3);
 static struct gpio_t gpio_rffc5072_reset	= GPIO(2, 14);
 
+/*
 static struct gpio_t gpio_sync_in_a		= GPIO(3,  8);
 static struct gpio_t gpio_sync_in_b		= GPIO(3,  9);
 static struct gpio_t gpio_sync_out_a		= GPIO(3, 10);
 static struct gpio_t gpio_sync_out_b		= GPIO(3, 11);
+*/
+static struct gpio_t gpio_sync_in_a		= GPIO(3,  10);
+static struct gpio_t gpio_sync_in_b		= GPIO(3,  11);
+static struct gpio_t gpio_sync_out_a		= GPIO(3, 8);
+static struct gpio_t gpio_sync_out_b		= GPIO(3, 9);
 #endif
 
 /* RF LDO control */
@@ -846,6 +852,12 @@ void pin_setup(void) {
 
 	/* Safe state: start with VAA turned off: */
 	disable_rf_power();
+
+	gpio_input(&gpio_sync_in_a);
+	gpio_input(&gpio_sync_in_b);
+
+	gpio_output(&gpio_sync_out_a);
+	gpio_output(&gpio_sync_out_b);
 #endif
 
 	/* enable input on SCL and SDA pins */
@@ -897,6 +909,24 @@ void hw_sync_start() {
 	gpio_set(&gpio_sync_out_b);
 }
 
+void hw_sync_stop() {
+	gpio_clear(&gpio_sync_out_a);
+	gpio_clear(&gpio_sync_out_b);
+}
+
+void hw_sync_copy_state() {
+	if(gpio_read(&gpio_sync_in_a)) {
+		gpio_set(&gpio_sync_out_a);
+	} else {
+		gpio_clear(&gpio_sync_out_a);
+	}
+	if(gpio_read(&gpio_sync_in_b)) {
+		gpio_set(&gpio_sync_out_b);
+	} else {
+		gpio_clear(&gpio_sync_out_b);
+	}
+}
+
 bool hw_sync_ready() {
 	return (gpio_read(&gpio_sync_in_a) && gpio_read(&gpio_sync_in_b));
 }
diff --git a/firmware/common/hackrf_core.h b/firmware/common/hackrf_core.h
index e83a6266..4458a65d 100644
--- a/firmware/common/hackrf_core.h
+++ b/firmware/common/hackrf_core.h
@@ -272,7 +272,10 @@ void led_off(const led_t led);
 void led_toggle(const led_t led);
 
 void hw_sync_start();
+void hw_sync_stop();
 bool hw_sync_ready();
+void hw_sync_copy_state();
+
 
 #ifdef __cplusplus
 }
diff --git a/firmware/hackrf_usb/hackrf_usb.c b/firmware/hackrf_usb/hackrf_usb.c
index 11411461..adcdbcab 100644
--- a/firmware/hackrf_usb/hackrf_usb.c
+++ b/firmware/hackrf_usb/hackrf_usb.c
@@ -252,20 +252,27 @@ int main(void) {
 	int hw_sync_count = 0;
 
 	unsigned int phase = 0;
+
+	hw_sync_start();
 	while(true) {
 		// Check whether we need to initiate a CPLD update
 		if (start_cpld_update)
 			cpld_update();
 
 
+		hw_sync_copy_state();
+
 		// check for hardware sync
 		if(hw_sync_ready()) {
 			synced = true;
-			hw_sync_start();
-		} /*else if(hw_sync_count++ > 1000) {
+			//hw_sync_start();
+		} else if(hw_sync_count++ > 1000000) {
+			//hw_sync_stop();
 			led_toggle(LED3);
 			hw_sync_count = 0;
-		}*/
+		} else if(hw_sync_count == 500000) {
+			//hw_sync_start();
+		}
 
 		//int gpio_sync_in_flag = gpio_get(gpio_sync_in);
 
@@ -276,7 +283,8 @@ int main(void) {
 			usb_transfer_schedule_block(
 				(transceiver_mode() == TRANSCEIVER_MODE_RX)
 				? &usb_endpoint_bulk_in : &usb_endpoint_bulk_out,
-				synced ? &usb_bulk_buffer[0x0000] : &usb_dummy_buffer[0x0000],
+				//synced ? &usb_bulk_buffer[0x0000] : &usb_dummy_buffer[0x0000],
+				&usb_bulk_buffer[0x0000],
 				0x4000,
 				NULL, NULL
 				);
@@ -290,7 +298,8 @@ int main(void) {
 			usb_transfer_schedule_block(
 				(transceiver_mode() == TRANSCEIVER_MODE_RX)
 				? &usb_endpoint_bulk_in : &usb_endpoint_bulk_out,
-				synced ? &usb_bulk_buffer[0x4000] : &usb_dummy_buffer[0x4000],
+				//synced ? &usb_bulk_buffer[0x4000] : &usb_dummy_buffer[0x4000],
+				&usb_bulk_buffer[0x4000],
 				0x4000,
 				NULL, NULL
 			);