diff --git a/src/ledmatrixdisplay.cpp b/src/ledmatrixdisplay.cpp
index ad484e34..3e273731 100644
--- a/src/ledmatrixdisplay.cpp
+++ b/src/ledmatrixdisplay.cpp
@@ -206,7 +206,7 @@ uint8_t GetCharWidth(char cChar) {
 }
 
 void ScrollMatrixLeft(uint8_t *buf, const uint16_t cols, const uint16_t rows) {
-  uint32_t i, k, idx;
+  uint32_t i, k, idx = 0;
   const uint32_t x = cols / 8;
 
   for (k = 0; k < rows; k++) {
diff --git a/src/lmic_config.h b/src/lmic_config.h
index 4a48283e..9a955dc1 100644
--- a/src/lmic_config.h
+++ b/src/lmic_config.h
@@ -22,6 +22,12 @@
 #define LMIC_USE_INTERRUPTS 1
 #endif
 
+// avoid lmic warning if we don't configure radio because we don't have one
+#define CFG_sx1276_radio 1
+#if ! (defined(CFG_sx1272_radio) || defined(CFG_sx1276_radio))
+#define CFG_sx1276_radio 1
+#endif
+
 // time sync via LoRaWAN network, note: not supported by TTNv2
 #define LMIC_ENABLE_DeviceTimeReq 1
 
diff --git a/src/lorawan.cpp b/src/lorawan.cpp
index 040e9805..6178580d 100644
--- a/src/lorawan.cpp
+++ b/src/lorawan.cpp
@@ -136,9 +136,9 @@ void RevBytes(unsigned char *b, size_t c) {
 }
 
 // LMIC callback functions
-void os_getDevKey(u1_t *buf) { 
+void os_getDevKey(u1_t *buf) {
 #ifndef LORA_ABP
-  memcpy(buf, APPKEY, 16); 
+  memcpy(buf, APPKEY, 16);
 #endif
 }
 
@@ -306,30 +306,30 @@ esp_err_t lora_stack_init(bool do_join) {
                           &lmicTask,  // task handle
                           1);         // CPU core
 
-  #ifdef LORA_ABP
-    // Pass ABP parameters to LMIC_setSession
+#ifdef LORA_ABP
+  // Pass ABP parameters to LMIC_setSession
+  LMIC_reset();
+  uint8_t appskey[sizeof(APPSKEY)];
+  uint8_t nwkskey[sizeof(NWKSKEY)];
+  memcpy_P(appskey, APPSKEY, sizeof(APPSKEY));
+  memcpy_P(nwkskey, NWKSKEY, sizeof(NWKSKEY));
+  LMIC_setSession(NETID, DEVADDR, nwkskey, appskey);
+  // These parameters are defined as macro in loraconf.h
+  setABPParamaters();
+#else
+  // Start join procedure if not already joined,
+  // lora_setupForNetwork(true) is called by eventhandler when joined
+  // else continue current session
+  if (do_join) {
+    if (!LMIC_startJoining())
+      ESP_LOGI(TAG, "Already joined");
+  } else {
     LMIC_reset();
-    uint8_t appskey[sizeof(APPSKEY)];
-    uint8_t nwkskey[sizeof(NWKSKEY)];
-    memcpy_P(appskey, APPSKEY, sizeof(APPSKEY));
-    memcpy_P(nwkskey, NWKSKEY, sizeof(NWKSKEY));
-    LMIC_setSession (NETID, DEVADDR, nwkskey, appskey);
-    // These parameters are defined as macro in loraconf.h
-    setABPParamaters();
-  #else
-    // Start join procedure if not already joined,
-    // lora_setupForNetwork(true) is called by eventhandler when joined
-    // else continue current session
-    if (do_join) {
-      if (!LMIC_startJoining())
-        ESP_LOGI(TAG, "Already joined");
-    } else {
-      LMIC_reset();
-      LMIC_setSession(RTCnetid, RTCdevaddr, RTCnwkKey, RTCartKey);
-      LMIC.seqnoUp = RTCseqnoUp;
-      LMIC.seqnoDn = RTCseqnoDn;
-    }
-  #endif
+    LMIC_setSession(RTCnetid, RTCdevaddr, RTCnwkKey, RTCartKey);
+    LMIC.seqnoUp = RTCseqnoUp;
+    LMIC.seqnoDn = RTCseqnoDn;
+  }
+#endif
   // start lmic send task
   xTaskCreatePinnedToCore(lora_send,      // task function
                           "lorasendtask", // name of task
diff --git a/src/timesync.cpp b/src/timesync.cpp
index a44ab138..d0bc4c5d 100644
--- a/src/timesync.cpp
+++ b/src/timesync.cpp
@@ -170,6 +170,8 @@ void timesync_store(uint32_t timestamp, timesync_t timestamp_type) {
 // callback function to receive time answer from network or answer
 void IRAM_ATTR timesync_serverAnswer(void *pUserData, int flag) {
 
+#if (TIME_SYNC_LORASERVER) || (TIME_SYNC_LORAWAN)
+
   // if no timesync handshake is pending then exit
   if (!timeSyncPending)
     return;
@@ -269,4 +271,6 @@ Exit:
   // inform processing task
   xTaskNotify(timeSyncProcTask, (rc ? rcv_seqNo : TIME_SYNC_END_FLAG),
               eSetBits);
+
+#endif // (TIME_SYNC_LORASERVER) || (TIME_SYNC_LORAWAN)
 }
\ No newline at end of file