diff --git a/src/knx/coupler/bau091A.cpp b/src/knx/coupler/bau091A.cpp
index 59f168a..eda8fae 100644
--- a/src/knx/coupler/bau091A.cpp
+++ b/src/knx/coupler/bau091A.cpp
@@ -188,18 +188,25 @@ namespace Knx
         {
             // ACK for broadcasts
             if (address == 0)
+            {
                 ack = TPAckType::AckReqAck;
-
-            if (lcconfig & LCCONFIG::GROUP_IACK_ROUT)
-
-                // is group address in filter table? ACK if yes, No if not
-                if (_netLayer.isRoutedGroupAddress(address, 1))
-                    ack = TPAckType::AckReqAck;
-                else
-                    ack = TPAckType::AckReqNone;
+            }
             else
-                // all are ACKED
-                ack = TPAckType::AckReqAck;
+            {
+                if (lcconfig & LCCONFIG::GROUP_IACK_ROUT)
+                {
+                    // is group address in filter table? ACK if yes, No if not
+                    if (_netLayer.isRoutedGroupAddress(address, 1))
+                        ack = TPAckType::AckReqAck;
+                    else
+                        ack = TPAckType::AckReqNone;
+                }
+                else
+                {
+                    // all are ACKED
+                    ack = TPAckType::AckReqAck;
+                }
+            }
 
 #ifdef KNX_TUNNELING
 
diff --git a/src/knx/interface_object/device_object.h b/src/knx/interface_object/device_object.h
index eeb68c5..c7167cf 100644
--- a/src/knx/interface_object/device_object.h
+++ b/src/knx/interface_object/device_object.h
@@ -11,7 +11,7 @@ namespace Knx
         public:
             // increase this version anytime DeviceObject-API changes
             // the following value represents the serialized representation of DeviceObject.
-            const uint16_t apiVersion = 1;
+            const uint16_t apiVersion = 2;
 
             DeviceObject();
             uint8_t* save(uint8_t* buffer) override;
diff --git a/src/knx/ip/ip_data_link_layer.cpp b/src/knx/ip/ip_data_link_layer.cpp
index b8c6055..28a19f5 100644
--- a/src/knx/ip/ip_data_link_layer.cpp
+++ b/src/knx/ip/ip_data_link_layer.cpp
@@ -500,8 +500,6 @@ namespace Knx
 
         if (searchRequest.srpRequestDIBs)
         {
-            println("srpRequestDIBs");
-
             if (searchRequest.requestedDIB(IP_CONFIG))
                 dibLength += LEN_IP_CONFIG_DIB; //16
 
@@ -556,9 +554,9 @@ namespace Knx
 #endif
         }
 
-        if (searchResponse.totalLength() > 150)
+        if (searchResponse.totalLength() > 500)
         {
-            println("skipped response cause length is not plausible");
+            printf("skipped response length > 500. Length: %d bytes\n", searchResponse.totalLength());
             return;
         }
 
@@ -716,7 +714,7 @@ namespace Knx
             }
 
 
-            if (tunnelResActive[i])  // tunnel reserve feature active for this tunnel
+            if (resTunActive && tunnelResActive[i])  // tunnel reserve feature active for this tunnel
             {
 #ifdef KNX_LOG_TUNNELING
                 print("tunnel reserve feature active for this tunnel: ");
@@ -835,7 +833,8 @@ namespace Knx
                     break;
                 }
 
-            tun->IndividualAddress = tunPa;
+            if (tun)
+                tun->IndividualAddress = tunPa;
         }
 
         if (tun == nullptr)
@@ -869,9 +868,9 @@ namespace Knx
             _lastChannelId = 0;
 
         tun->IpAddress = srcIP;
-        tun->PortData = srcPort;
-        tun->PortCtrl = connRequest.hpaiCtrl().ipPortNumber() ? connRequest.hpaiCtrl().ipPortNumber() : srcPort;
-
+        tun->PortData = connRequest.hpaiData().ipPortNumber()?connRequest.hpaiData().ipPortNumber():srcPort;
+        tun->PortCtrl = connRequest.hpaiCtrl().ipPortNumber()?connRequest.hpaiCtrl().ipPortNumber():srcPort;
+    
         print("New Tunnel-Connection[");
         print(tunIdx);
         print("], Channel: 0x");
diff --git a/src/knx/ip/ip_data_link_layer.h b/src/knx/ip/ip_data_link_layer.h
index 3b61029..45380d5 100644
--- a/src/knx/ip/ip_data_link_layer.h
+++ b/src/knx/ip/ip_data_link_layer.h
@@ -52,7 +52,7 @@ namespace Knx
             DataLinkLayerCallbacks* _dllcb;
 #ifdef KNX_TUNNELING
             KnxIpTunnelConnection tunnels[KNX_TUNNELING];
-            uint8_t _lastChannelId = 1;
+            uint8_t _lastChannelId = 0;
 #endif
     };
 }
\ No newline at end of file
diff --git a/src/knx/ip/knx_ip_connect_response.cpp b/src/knx/ip/knx_ip_connect_response.cpp
index f760a4c..5811bd6 100644
--- a/src/knx/ip/knx_ip_connect_response.cpp
+++ b/src/knx/ip/knx_ip_connect_response.cpp
@@ -18,7 +18,9 @@ namespace Knx
 
         _crd.length((type == 4) ? 4 : 2); //TunnelConnectionResponse length = 4; ConfigConnectionResponse length = 2;
         _crd.type(type);
-        _crd.address(address);
+
+        if (type == 4) // only fill address when it is a TunnelConnectionResponse
+            _crd.address(address);
     }
 
     KnxIpConnectResponse::KnxIpConnectResponse(uint8_t channel, uint8_t errorCode)
diff --git a/src/knx/ip/knx_ip_search_response_extended.cpp b/src/knx/ip/knx_ip_search_response_extended.cpp
index 52d9b0e..02d8490 100644
--- a/src/knx/ip/knx_ip_search_response_extended.cpp
+++ b/src/knx/ip/knx_ip_search_response_extended.cpp
@@ -36,7 +36,6 @@ namespace Knx
 
     void KnxIpSearchResponseExtended::setDeviceInfo(IpParameterObject& parameters, DeviceObject& deviceObject)
     {
-        println("setDeviceInfo");
         KnxIpDeviceInformationDIB _deviceInfo(_data + currentPos);
         _deviceInfo.length(LEN_DEVICE_INFORMATION_DIB);
         _deviceInfo.code(DEVICE_INFO);
@@ -67,7 +66,6 @@ namespace Knx
 
     void KnxIpSearchResponseExtended::setSupportedServices()
     {
-        println("setSupportedServices");
         KnxIpSupportedServiceDIB _supportedServices(_data + currentPos);
         _supportedServices.length(LEN_SERVICE_DIB);
         _supportedServices.code(SUPP_SVC_FAMILIES);
@@ -84,7 +82,6 @@ namespace Knx
 
     void KnxIpSearchResponseExtended::setIpConfig(IpParameterObject& parameters)
     {
-        println("setIpConfig");
         KnxIpConfigDIB _ipConfig(_data + currentPos);
         _ipConfig.length(LEN_IP_CONFIG_DIB);
         _ipConfig.code(IP_CONFIG);
@@ -99,7 +96,6 @@ namespace Knx
 
     void KnxIpSearchResponseExtended::setIpCurrentConfig(IpParameterObject& parameters)
     {
-        println("setIpCurrentConfig");
         KnxIpConfigDIB _ipCurConfig(_data + currentPos, true);
         _ipCurConfig.length(LEN_IP_CURRENT_CONFIG_DIB);
         _ipCurConfig.code(IP_CUR_CONFIG);
@@ -115,7 +111,6 @@ namespace Knx
 
     void KnxIpSearchResponseExtended::setKnxAddresses(IpParameterObject& parameters, DeviceObject& deviceObject)
     {
-        println("setKnxAddresses");
         KnxIpKnxAddressesDIB _knxAddresses(_data + currentPos);
         _knxAddresses.length(4); //minimum
         _knxAddresses.code(KNX_ADDRESSES);
@@ -138,7 +133,6 @@ namespace Knx
 #ifdef KNX_TUNNELING
     void KnxIpSearchResponseExtended::setTunnelingInfo(IpParameterObject& parameters, DeviceObject& deviceObject, KnxIpTunnelConnection tunnels[])
     {
-        println("setTunnelingInfo");
         KnxIpTunnelingInfoDIB _tunnelInfo(_data + currentPos);
         _tunnelInfo.length(4); //minlength
         _tunnelInfo.code(TUNNELING_INFO);
@@ -204,7 +198,6 @@ namespace Knx
 #endif
     void KnxIpSearchResponseExtended::setExtendedDeviceInfo()
     {
-        println("setExtendedDeviceInfo");
         KnxIpExtendedDeviceInformationDIB _extended(_data + currentPos);
         _extended.length(LEN_EXTENDED_DEVICE_INFORMATION_DIB);
         _extended.code(EXTENDED_DEVICE_INFO);
diff --git a/src/knx/platform/esp32_platform.cpp b/src/knx/platform/esp32_platform.cpp
index 1552ffc..e123ec4 100644
--- a/src/knx/platform/esp32_platform.cpp
+++ b/src/knx/platform/esp32_platform.cpp
@@ -1,4 +1,5 @@
 #ifdef ARDUINO_ARCH_ESP32
+#pragma once
 #include "esp32_platform.h"
 
 #include <Arduino.h>
@@ -8,7 +9,17 @@
 
 #ifndef KNX_SERIAL
     #define KNX_SERIAL Serial1
+    #pragma warn "KNX_SERIAL not defined, using Serial1"
 #endif
+ 
+#ifdef KNX_IP_LAN
+    #include "ETH.h"
+    #define KNX_NETIF ETH
+#else // KNX_IP_WIFI
+    #include <WiFi.h>
+    #define KNX_NETIF WiFi
+#endif
+
 
 namespace Knx
 {
@@ -46,17 +57,17 @@ namespace Knx
 
     uint32_t Esp32Platform::currentIpAddress()
     {
-        return WiFi.localIP();
+        return KNX_NETIF.localIP();
     }
 
     uint32_t Esp32Platform::currentSubnetMask()
     {
-        return WiFi.subnetMask();
+        return KNX_NETIF.subnetMask();
     }
 
     uint32_t Esp32Platform::currentDefaultGateway()
     {
-        return WiFi.gatewayIP();
+        return KNX_NETIF.gatewayIP();
     }
 
     void Esp32Platform::macAddress(uint8_t* addr)
@@ -83,7 +94,7 @@ namespace Knx
         IPAddress mcastaddr(htonl(addr));
 
         KNX_DEBUG_SERIAL.printf("setup multicast addr: %s port: %d ip: %s\n", mcastaddr.toString().c_str(), port,
-                                WiFi.localIP().toString().c_str());
+                                KNX_NETIF.localIP().toString().c_str());
         uint8_t result = _udp.beginMulticast(mcastaddr, port);
         KNX_DEBUG_SERIAL.printf("result %d\n", result);
     }
diff --git a/src/knx/platform/esp32_platform.h b/src/knx/platform/esp32_platform.h
index 660afd4..7190554 100644
--- a/src/knx/platform/esp32_platform.h
+++ b/src/knx/platform/esp32_platform.h
@@ -1,9 +1,7 @@
 #ifdef ARDUINO_ARCH_ESP32
 #include "arduino_platform.h"
-#include <WiFi.h>
 #include <WiFiUdp.h>
 
-
 namespace Knx
 {
     class Esp32Platform : public ArduinoPlatform
diff --git a/src/knx/platform/rp2040_arduino_platform.cpp b/src/knx/platform/rp2040_arduino_platform.cpp
index 37c5f51..87bd9ea 100644
--- a/src/knx/platform/rp2040_arduino_platform.cpp
+++ b/src/knx/platform/rp2040_arduino_platform.cpp
@@ -471,12 +471,7 @@ namespace Knx
     }
     void RP2040ArduinoPlatform::macAddress(uint8_t* addr)
     {
-#if defined(KNX_IP_LAN)
-        addr = KNX_NETIF.getNetIf()->hwaddr;
-#else
-        uint8_t macaddr[6] = {0, 0, 0, 0, 0, 0};
-        addr = KNX_NETIF.macAddress(macaddr);
-#endif
+        KNX_NETIF.macAddress(addr);
     }
 
     // multicast
diff --git a/src/knx/tp/tpuart_data_link_layer.cpp b/src/knx/tp/tpuart_data_link_layer.cpp
index 4a42657..d999a51 100644
--- a/src/knx/tp/tpuart_data_link_layer.cpp
+++ b/src/knx/tp/tpuart_data_link_layer.cpp
@@ -636,6 +636,15 @@ namespace Knx
         if (markerMode())
             _platform.writeUart(U_CONFIGURE_REQ | U_CONFIGURE_MARKER_REQ);
 
+#endif
+
+        // Set Address for AutoACK Unicast
+        const uint16_t address = _deviceObject.individualAddress();
+        _platform.writeUart(U_SET_ADDRESS_REQ);
+        _platform.writeUart((address >> 8) & 0xFF);
+        _platform.writeUart(address & 0xFF);
+#ifdef NCN5120
+        _platform.writeUart(0xFF); // Dummy Byte needed by NCN only
 #endif
 
         // Deviating Config