diff --git a/device.h b/device.h
index 19907e0..3c4bd47 100755
--- a/device.h
+++ b/device.h
@@ -10,7 +10,7 @@
 
 // Voltage references
 // TODO: Determine best defaults
-#define CONFIG_ADC_REF 128
+#define CONFIG_ADC_REF 255
 #define CONFIG_DAC_REF 255
 
 // TODO: Change this back to default
@@ -25,9 +25,9 @@
 // Serial settings
 #define SERIAL_DEBUG false
 #define TX_MAXWAIT 2UL
-#define CONFIG_QUEUE_SIZE 3000 // TODO: Optimise this by saving ram other places, add SD queue
+#define CONFIG_QUEUE_SIZE 6000 // TODO: Optimise this by saving ram other places, add SD queue
 #define CONFIG_QUEUE_MAX_LENGTH 15
-#define CONFIG_SERIAL_BUFFER_SIZE 1532 // TODO: Tune this, what is actually required?
+#define CONFIG_SERIAL_BUFFER_SIZE 1536 // TODO: Tune this, what is actually required?
 #define CONFIG_SERIAL_TIMEOUT_MS 10
 #define CONFIG_BENCHMARK_MODE false
 
@@ -36,7 +36,7 @@
 #define CONFIG_CSMA_P 255
 
 #define AX25_MIN_FRAME_LEN 1
-#define AX25_MAX_FRAME_LEN 1532
+#define AX25_MAX_FRAME_LEN 600
 
 // Packet settings
 #define CONFIG_PASSALL false
diff --git a/hardware/AFSK.h b/hardware/AFSK.h
index acdb065..5c6fae3 100755
--- a/hardware/AFSK.h
+++ b/hardware/AFSK.h
@@ -40,7 +40,7 @@ inline static uint8_t sinSample(uint16_t i) {
 #define CPU_FREQ F_CPU
 
 
-#define BITRATE 1200
+#define BITRATE 2400
 
 #if BITRATE == 300
     #define CONFIG_ADC_SAMPLERATE 9600UL
diff --git a/hardware/Bluetooth.h b/hardware/Bluetooth.h
index 8cc3dd7..05841e2 100644
--- a/hardware/Bluetooth.h
+++ b/hardware/Bluetooth.h
@@ -14,6 +14,4 @@ void bluetooth_init(void);
 bool bluetooth_enabled(void);
 
 
-#endif
-
-// CMD/DATA sequence: 0x2b2b2b0d
+#endif
\ No newline at end of file
diff --git a/hardware/Serial.c b/hardware/Serial.c
index 7dc417c..b94406d 100755
--- a/hardware/Serial.c
+++ b/hardware/Serial.c
@@ -2,6 +2,8 @@
 #include <stdio.h>
 #include <string.h>
 
+extern volatile uint8_t queue_height;
+
 void serial_init(Serial *serial) {
     memset(serial, 0, sizeof(*serial));
     memset(serialBuf, 0, sizeof(serialBuf));
@@ -47,8 +49,19 @@ char uart0_getchar_nowait(void) {
 ISR(USART0_RX_vect) {
     if (serial_available(0)) {
         LED_COM_ON();
-        char c = uart0_getchar_nowait();
-        fifo_push(&serialFIFO, c);
+        if (!fifo_isfull(&serialFIFO)) {
+            char c = uart0_getchar_nowait();
+            fifo_push(&serialFIFO, c);
+        } else {
+            // TODO: Remove this
+            printf("SERIAL FIFO OVERRUN\r\n");
+            printf("QH: %d", queue_height);
+            while(true) {
+                LED_TX_ON();
+                LED_RX_ON();
+                LED_COM_ON();
+            }
+        }
     }
 }
 
diff --git a/protocol/KISS.c b/protocol/KISS.c
index 55fa59e..3210c16 100755
--- a/protocol/KISS.c
+++ b/protocol/KISS.c
@@ -162,14 +162,6 @@ void kiss_flushQueue(void) {
     }
 }
 
-uint8_t kiss_queuedPackets(void) {
-    return 0;
-}
-
-bool kiss_queueIsFull(void) {
-    return false;
-}
-
 void kiss_serialCallback(uint8_t sbyte) {
     if (IN_FRAME && sbyte == FEND && command == CMD_DATA) {
         IN_FRAME = false;
@@ -184,7 +176,7 @@ void kiss_serialCallback(uint8_t sbyte) {
             fifo16_push_locked(&packet_lengths, l);
 
             current_packet_start = queue_cursor;
-            //printf("Queue height %d\r\n", queue_height);
+            printf("Queue height %d\r\n", queue_height);
         }
         
     } else if (sbyte == FEND) {