diff --git a/src/knx/bau.h b/src/knx/bau.h
index e13af25..d2d6ada 100644
--- a/src/knx/bau.h
+++ b/src/knx/bau.h
@@ -109,7 +109,7 @@ class BusAccessUnit
     virtual void keyWriteResponseConfirm(AckType ack, Priority priority, HopCountType hopType, uint16_t asap, uint8_t level,
                                          bool status);
     virtual void keyWriteAppLayerConfirm(Priority priority, HopCountType hopType, uint16_t asap, uint8_t level);
-    virtual bool connectConfirm(uint16_t destination);
+    virtual void connectConfirm(uint16_t destination);
     virtual void systemNetworkParameterReadIndication(Priority priority, HopCountType hopType, uint16_t objectType,
                                                       uint16_t propertyId, uint8_t* testInfo, uint16_t testInfoLength);
 
diff --git a/src/knx/knx_types.h b/src/knx/knx_types.h
index 25afe8a..0421526 100644
--- a/src/knx/knx_types.h
+++ b/src/knx/knx_types.h
@@ -116,13 +116,3 @@ enum ApduType
     PropertyDescriptionRead = 0x3d8,
     PropertyDescriptionResponse = 0x3d9,
 };
-
-enum KnxMediumType
-{
-    KnxMediumType_TP1 = 0,
-    KnxMediumType_PL = 1,
-    KnxMediumType_RF = 2,
-    KnxMediumType_TP0 = 3,   // not supported anymore
-    KnxMediumType_PL132 = 4, // not supported anymore
-    KnxMediumType_IP = 5,
-};
\ No newline at end of file