diff --git a/flight/Modules/Guidance/guidance.c b/flight/Modules/Guidance/guidance.c
index a507c4cc2..6ac960c9b 100644
--- a/flight/Modules/Guidance/guidance.c
+++ b/flight/Modules/Guidance/guidance.c
@@ -174,7 +174,8 @@ static void guidanceTask(void *parameters)
 		if ( (systemSettings.AirframeType != SYSTEMSETTINGS_AIRFRAMETYPE_VTOL) &&
 		     (systemSettings.AirframeType != SYSTEMSETTINGS_AIRFRAMETYPE_QUADP) &&
 		     (systemSettings.AirframeType != SYSTEMSETTINGS_AIRFRAMETYPE_QUADX) &&
-		     (systemSettings.AirframeType != SYSTEMSETTINGS_AIRFRAMETYPE_HEXA) )
+		     (systemSettings.AirframeType != SYSTEMSETTINGS_AIRFRAMETYPE_HEXA) &&
+		     (systemSettings.AirframeType != SYSTEMSETTINGS_AIRFRAMETYPE_HEXACOAX) )
 		{
 			AlarmsSet(SYSTEMALARMS_ALARM_GUIDANCE,SYSTEMALARMS_ALARM_WARNING);
 			continue;
diff --git a/flight/PiOS/STM32F4xx/pios_usb.c b/flight/PiOS/STM32F4xx/pios_usb.c
index 5369ea672..c040fb0e5 100644
--- a/flight/PiOS/STM32F4xx/pios_usb.c
+++ b/flight/PiOS/STM32F4xx/pios_usb.c
@@ -217,7 +217,7 @@ void USB_OTG_BSP_EnableInterrupt(USB_OTG_CORE_HANDLE *pdev)
 	bool valid = PIOS_USB_validate(usb_dev);
 	PIOS_Assert(valid);
 
-	NVIC_PriorityGroupConfig(NVIC_PriorityGroup_1);
+	NVIC_PriorityGroupConfig(NVIC_PriorityGroup_4);
 
 	NVIC_Init(&usb_dev->cfg->irq.init);
 }
diff --git a/flight/Revolution/System/inc/pios_config.h b/flight/Revolution/System/inc/pios_config.h
index 045fd13ea..484b0ed60 100644
--- a/flight/Revolution/System/inc/pios_config.h
+++ b/flight/Revolution/System/inc/pios_config.h
@@ -98,8 +98,8 @@
 #define PIOS_GPS_SETS_HOMELOCATION      /* GPS options */
 
 /* Alarm Thresholds */
-#define HEAP_LIMIT_WARNING		500
-#define HEAP_LIMIT_CRITICAL		1000
+#define HEAP_LIMIT_WARNING		1000
+#define HEAP_LIMIT_CRITICAL		500
 #define IRQSTACK_LIMIT_WARNING		150
 #define IRQSTACK_LIMIT_CRITICAL		80
 #define CPULOAD_LIMIT_WARNING		80