diff --git a/src/lorawan.cpp b/src/lorawan.cpp
index 1e8c641f..5d8359d5 100644
--- a/src/lorawan.cpp
+++ b/src/lorawan.cpp
@@ -437,7 +437,7 @@ esp_err_t lora_stack_init() {
                           "lmictask", // name of task
                           4096,       // stack size of task
                           (void *)1,  // parameter of the task
-                          2,          // priority of the task
+                          5,          // priority of the task
                           &lmicTask,  // task handle
                           1);         // CPU core
 
diff --git a/src/main.cpp b/src/main.cpp
index 2937f793..c6eb2867 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -31,9 +31,9 @@ ledloop       0     3     blinks LEDs
 spiloop       0     2     reads/writes data on spi interface
 IDLE          0     0     ESP32 arduino scheduler -> runs wifi sniffer
 
+lmictask      1     5     MCCI LMiC LORAWAN stack
 clockloop     1     4     generates realtime telegrams for external clock
 timesync_req  1     3     processes realtime time sync requests
-lmictask      1     2     MCCI LMiC LORAWAN stack
 irqhandler    1     1     display, timesync, gps, etc. triggered by timers
 gpsloop       1     1     reads data from GPS via serial or i2c
 lorasendtask  1     1     feed data from lora sendqueue to lmcic
@@ -58,6 +58,7 @@ fired by hardware
 DisplayIRQ      -> esp32 timer 0  -> irqHandlerTask (Core 1)
 CLOCKIRQ        -> esp32 timer 1  -> ClockTask (Core 1)
 ButtonIRQ       -> external gpio  -> irqHandlerTask (Core 1)
+PMUIRQ          -> PMU chip gpio  -> irqHandlerTask (Core 1)
 
 fired by software (Ticker.h)
 TIMESYNC_IRQ    -> timeSync()     -> irqHandlerTask (Core 1)
diff --git a/src/wifiscan.cpp b/src/wifiscan.cpp
index 3695508f..b22fe5f2 100644
--- a/src/wifiscan.cpp
+++ b/src/wifiscan.cpp
@@ -72,6 +72,7 @@ void wifi_sniffer_init(void) {
       esp_wifi_set_storage(WIFI_STORAGE_RAM)); // we don't need NVRAM
   ESP_ERROR_CHECK(esp_wifi_set_mode(WIFI_MODE_NULL));
   ESP_ERROR_CHECK(esp_wifi_set_ps(WIFI_PS_NONE)); // no modem power saving
+  ESP_ERROR_CHECK(esp_wifi_start()); // must be started to be able to switch ch
   ESP_ERROR_CHECK(esp_wifi_set_promiscuous_filter(&filter)); // set frame filter
   ESP_ERROR_CHECK(esp_wifi_set_promiscuous_rx_cb(&wifi_sniffer_packet_handler));
   ESP_ERROR_CHECK(esp_wifi_set_promiscuous(true)); // now switch on monitor mode