diff --git a/DMRDirectNetwork.cpp b/DMRDirectNetwork.cpp
index 8bb397f..4ed871c 100644
--- a/DMRDirectNetwork.cpp
+++ b/DMRDirectNetwork.cpp
@@ -31,6 +31,8 @@ const unsigned int HOMEBREW_DATA_PACKET_LENGTH = 55U;
 
 
 CDMRDirectNetwork::CDMRDirectNetwork(const std::string& address, unsigned int port, unsigned int local, unsigned int id, const std::string& password, bool duplex, const char* version, bool slot1, bool slot2, HW_TYPE hwType, bool debug) :
+m_address(address),
+m_port(port),
 m_addr(),
 m_addrLen(0U),
 m_id(NULL),
@@ -70,9 +72,6 @@ m_beacon(false)
 	assert(id > 1000U);
 	assert(!password.empty());
 
-	if (CUDPSocket::lookup(address, port, m_addr, m_addrLen) != 0)
-		m_addrLen = 0U;
-
 	m_buffer   = new unsigned char[BUFFER_LENGTH];
 	m_salt     = new unsigned char[sizeof(uint32_t)];
 	m_id       = new uint8_t[4U];
@@ -122,7 +121,7 @@ void CDMRDirectNetwork::setConfig(const std::string& callsign, unsigned int rxFr
 
 bool CDMRDirectNetwork::open()
 {
-	if (m_addrLen == 0U) {
+	if (CUDPSocket::lookup(m_address, m_port, m_addr, m_addrLen) != 0) {
 		LogError("DMR, Could not lookup the address of the DMR Network");
 		return false;
 	}
diff --git a/DMRDirectNetwork.h b/DMRDirectNetwork.h
index 896d5e4..30ba951 100644
--- a/DMRDirectNetwork.h
+++ b/DMRDirectNetwork.h
@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2015,2016,2017,2018,2020 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2015,2016,2017,2018,2020,2021 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -58,6 +58,8 @@ public:
 	virtual void close();
 
 private:
+	std::string      m_address;
+	unsigned int     m_port;
 	sockaddr_storage m_addr;
 	unsigned int     m_addrLen;
 	uint8_t*         m_id;
diff --git a/Display.cpp b/Display.cpp
index 16d34ea..ebb1864 100644
--- a/Display.cpp
+++ b/Display.cpp
@@ -677,7 +677,7 @@ CDisplay* CDisplay::createDisplay(const CConf& conf, CModem* modem)
 		bool          rotate     = conf.getOLEDRotate();
 		bool          logosaver  = conf.getOLEDLogoScreensaver();
 
-		display = new COLED(type, brightness, invert, scroll, rotate, logosaver, conf.getDMRNetworkSlot1(), conf.getDMRNetworkSlot2());
+		display = new COLED(type, brightness, invert, scroll, rotate, logosaver, conf.getDuplex());
 #endif
 	} else if (type == "CAST") {
 		display = new CCASTInfo(modem);
diff --git a/OLED.cpp b/OLED.cpp
index fe0b7b5..98b3e5f 100644
--- a/OLED.cpp
+++ b/OLED.cpp
@@ -191,15 +191,15 @@ const unsigned char logo_POCSAG_bmp [] =
 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff
 };
 
-COLED::COLED(unsigned char displayType, unsigned char displayBrightness, bool displayInvert, bool displayScroll, bool displayRotate, bool displayLogoScreensaver, bool slot1Enabled, bool slot2Enabled) :
+COLED::COLED(unsigned char displayType, unsigned char displayBrightness, bool displayInvert, bool displayScroll, bool displayRotate, bool displayLogoScreensaver, bool duplex) :
 m_displayType(displayType),
 m_displayBrightness(displayBrightness),
 m_displayInvert(displayInvert),
 m_displayScroll(displayScroll),
 m_displayRotate(displayRotate),
 m_displayLogoScreensaver(displayLogoScreensaver),
-m_slot1Enabled(slot1Enabled),
-m_slot2Enabled(slot2Enabled),
+m_duplex(duplex),
+//m_duplex(true),         // uncomment to force duplex display for testing!
 m_ipaddress(),
 m_display()
 {
@@ -403,7 +403,7 @@ int COLED::writeDMRIntEx(unsigned int slotNo, const class CUserDBentry& src, boo
     }
     // if both slots, use lines 2-3 for slot 1, lines 4-5 for slot 2
     // if single slot, use lines 2-3
-    if ( m_slot1Enabled && m_slot2Enabled ) {
+    if ( m_duplex ) {
 
         if (slotNo == 1U) {
             m_display.fillRect(0,OLED_LINE2,m_display.width(),40,BLACK);
@@ -451,7 +451,7 @@ void COLED::clearDMRInt(unsigned int slotNo)
 {
     // if both slots, use lines 2-3 for slot 1, lines 4-5 for slot 2
     // if single slot, use lines 2-3
-    if ( m_slot1Enabled && m_slot2Enabled ){
+    if ( m_duplex ){
         if (slotNo == 1U) {
             m_display.fillRect(0, OLED_LINE3, m_display.width(), 40, BLACK);
             m_display.setCursor(0,OLED_LINE3);
diff --git a/OLED.h b/OLED.h
index a7ab811..d14c5e1 100644
--- a/OLED.h
+++ b/OLED.h
@@ -41,7 +41,7 @@
 class COLED : public CDisplay 
 {
 public:
-  COLED(unsigned char displayType, unsigned char displayBrighness, bool displayInvert, bool displayScroll, bool displayRotate, bool displayLogoScreensaver, bool slot1Enabled, bool slot2Enabled);
+  COLED(unsigned char displayType, unsigned char displayBrighness, bool displayInvert, bool displayScroll, bool displayRotate, bool displayLogoScreensaver, bool duplex);
   virtual ~COLED();
 
   virtual bool open();
@@ -94,7 +94,7 @@ private:
   bool          m_displayScroll;
   bool          m_displayRotate;
   bool          m_displayLogoScreensaver;
-  bool          m_slot1Enabled;
+  bool          m_duplex;
   bool          m_slot2Enabled;
   std::string   m_ipaddress;
   ArduiPi_OLED  m_display;
diff --git a/Version.h b/Version.h
index f6215ae..7365a93 100644
--- a/Version.h
+++ b/Version.h
@@ -19,6 +19,6 @@
 #if !defined(VERSION_H)
 #define	VERSION_H
 
-const char* VERSION = "20210309";
+const char* VERSION = "20210312";
 
 #endif