diff --git a/flight/PipXtreme/api_config.c b/flight/PipXtreme/api_config.c
index 28019fe91..a8a319284 100644
--- a/flight/PipXtreme/api_config.c
+++ b/flight/PipXtreme/api_config.c
@@ -72,7 +72,7 @@ typedef struct
 
     uint32_t    min_frequency_Hz;
     uint32_t    max_frequency_Hz;
-    float	    frequency_Hz;
+    uint32_t    frequency_Hz;
 
     uint32_t    max_rf_bandwidth;
 
@@ -90,7 +90,7 @@ typedef struct
 
 typedef struct
 {
-    float	    start_frequency;
+	uint32_t	start_frequency;
     float	    frequency_step_size;
     uint16_t    magnitudes;
 //    int8_t      magnitude[0];
@@ -343,6 +343,7 @@ void apiconfig_process(void)
 	{	// the local communications port has changed .. remove any data in the buffers
 		apiconfig_rx_buffer_wr = 0;
 		apiconfig_tx_buffer_wr = 0;
+		apiconfig_tx_config_buffer_wr = 0;
 	}
 	else
 	if (usb_comms)
@@ -393,9 +394,10 @@ void apiconfig_process(void)
 			com_num--;
 		}
 
+		// scan for a configuration packet in the received data
 		uint16_t data_size = apiconfig_scanForConfigPacket(apiconfig_rx_buffer, &apiconfig_rx_buffer_wr, false);
 
-		if (data_size == 0 && apiconfig_rx_timer >= 10)
+		if (data_size == 0 && ((usb_comms && apiconfig_rx_timer >= 10) || ((!usb_comms && apiconfig_rx_timer >= 20))))
 		{	// no config packet found in the buffer within the timeout period, treat any data in the buffer as data to be sent over the air
 			data_size = apiconfig_rx_buffer_wr;
 		}
@@ -433,8 +435,8 @@ void apiconfig_process(void)
 		{
 			uint16_t data_size = apiconfig_tx_config_buffer_wr;
 
-			if (data_size > 32)
-				data_size = 32;
+//			if (data_size > 32)
+//				data_size = 32;
 
 			if (!usb_comms && !GPIO_IN(SERIAL_CTS_PIN))
 				break;	// we can't yet send data down the comm-port
diff --git a/flight/PipXtreme/inc/packet_handler.h b/flight/PipXtreme/inc/packet_handler.h
index 16c2efcaf..965b42305 100644
--- a/flight/PipXtreme/inc/packet_handler.h
+++ b/flight/PipXtreme/inc/packet_handler.h
@@ -45,8 +45,8 @@ uint16_t ph_putData(const int connection_index, const void *data, uint16_t len);
 uint16_t ph_getData_used(const int connection_index);
 uint16_t ph_getData(const int connection_index, void *data, uint16_t len);
 
-void ph_setNominalCarrierFrequency(float frequency_hz);
-float ph_getNominalCarrierFrequency(void);
+void ph_setNominalCarrierFrequency(uint32_t frequency_hz);
+uint32_t ph_getNominalCarrierFrequency(void);
 
 void ph_setDatarate(uint32_t datarate_bps);
 uint32_t ph_getDatarate(void);
diff --git a/flight/PipXtreme/inc/rfm22b.h b/flight/PipXtreme/inc/rfm22b.h
index fef1104e3..bf40f06ce 100644
--- a/flight/PipXtreme/inc/rfm22b.h
+++ b/flight/PipXtreme/inc/rfm22b.h
@@ -581,8 +581,8 @@ uint32_t rfm22_getDatarate(void);
 void rfm22_setTxPower(uint8_t tx_pwr);
 uint8_t rfm22_getTxPower(void);
 
-void rfm22_setNominalCarrierFrequency(float frequency_hz);
-float rfm22_getNominalCarrierFrequency(void);
+void rfm22_setNominalCarrierFrequency(uint32_t frequency_hz);
+uint32_t rfm22_getNominalCarrierFrequency(void);
 
 float rfm22_getFrequencyStepSize(void);
 
diff --git a/flight/PipXtreme/packet_handler.c b/flight/PipXtreme/packet_handler.c
index 6d5be42ac..ba62bfcd8 100644
--- a/flight/PipXtreme/packet_handler.c
+++ b/flight/PipXtreme/packet_handler.c
@@ -1383,12 +1383,12 @@ void ph_processLinks(int connection_index)
 // *****************************************************************************
 // set/get the carrier frequency
 
-void ph_setNominalCarrierFrequency(float frequency_hz)
+void ph_setNominalCarrierFrequency(uint32_t frequency_hz)
 {
 	rfm22_setNominalCarrierFrequency(frequency_hz);
 }
 
-float ph_getNominalCarrierFrequency(void)
+uint32_t ph_getNominalCarrierFrequency(void)
 {
 	return rfm22_getNominalCarrierFrequency();
 }
diff --git a/flight/PipXtreme/rfm22b.c b/flight/PipXtreme/rfm22b.c
index 2c8870c3c..cb7c19873 100644
--- a/flight/PipXtreme/rfm22b.c
+++ b/flight/PipXtreme/rfm22b.c
@@ -175,7 +175,7 @@ volatile uint8_t	rf_mode;							// holds our current RF mode
 
 uint32_t			lower_carrier_frequency_limit_Hz;	// the minimum RF frequency we can use
 uint32_t			upper_carrier_frequency_limit_Hz;	// the maximum RF frequency we can use
-float				carrier_frequency_hz;				// the current RF frequency we are on
+uint32_t			carrier_frequency_hz;				// the current RF frequency we are on
 
 uint32_t			carrier_datarate_bps;				// the RF data rate we are using
 
@@ -575,7 +575,7 @@ uint8_t rfm22_getTxPower(void)
 
 // ************************************
 
-void rfm22_setNominalCarrierFrequency(float frequency_hz)
+void rfm22_setNominalCarrierFrequency(uint32_t frequency_hz)
 {
 
 #if defined(RFM22_EXT_INT_USE)
@@ -629,7 +629,7 @@ void rfm22_setNominalCarrierFrequency(float frequency_hz)
 
 }
 
-float rfm22_getNominalCarrierFrequency(void)
+uint32_t rfm22_getNominalCarrierFrequency(void)
 {
     return carrier_frequency_hz;
 }
@@ -1574,7 +1574,7 @@ void rfm22_process(void)
 
 	if (power_on_reset)
 	{	// we need to re-initialize the RF module - it told us it's reset itself
-		float current_freq = carrier_frequency_hz;										// fetch current rf nominal frequency
+		uint32_t current_freq = carrier_frequency_hz;										// fetch current rf nominal frequency
 		uint32_t freq_hop_step_size = (uint32_t)frequency_hop_step_size_reg * 10000;	// fetch the frequency hoppping step size
 		rfm22_init(lower_carrier_frequency_limit_Hz, upper_carrier_frequency_limit_Hz, freq_hop_step_size);
 		rfm22_setNominalCarrierFrequency(current_freq);									// restore the nominal carrier frequency