EV_TXCOMPLETE Event missing

I've tried a simple example with APB and sending one Packet. But I never receive a EV_TXCOMPLETE Event. I checked If I get a IRQ on DIO0 from the Modem and this is working. But somehow the Library never triggers the EV_TXCOMPLETE Event. Is this a known problem in this Library port?

Tested on a TTGO LORA32.

My example:

#include <stdio.h>
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "sdkconfig.h"

#include <lmic.h>

static const u1_t NWKSKEY[16] = { };
static const u1_t APPSKEY[16] = { };
static const u4_t DEVADDR = ;

void os_getArtEui (u1_t* buf) { }
void os_getDevEui (u1_t* buf) { }
void os_getDevKey (u1_t* buf) { }

static uint8_t mydata[] = "1234";
static osjob_t sendjob;

const unsigned TX_INTERVAL = 1;

// Pin mapping
const lmic_pinmap lmic_pins = {
  .nss = 18,
  .rst = 14,
  .dio = { 26, 34, 35 },
  .spi = { /* MISO = */ 19, /* MOSI = */ 27, /* SCK = */ 5 },
  .rxtx = LMIC_UNUSED_PIN,
};

void do_send(osjob_t* j){
    // Check if there is not a current TX/RX job running
    if (LMIC.opmode & OP_TXRXPEND) {
        printf(("OP_TXRXPEND, not sending \n"));
    } else {
        // Prepare upstream data transmission at the next possible time.
        LMIC_setTxData2(1, mydata, sizeof(mydata)-1, 0);
        printf(("Packet queued \n"));
    }
    // Next TX is scheduled after TX_COMPLETE event.
}

void onEvent (ev_t ev) {
    printf(os_getTime());
    printf(": ");
    switch(ev) {
        case EV_SCAN_TIMEOUT:
            printf(("EV_SCAN_TIMEOUT"));
            break;
        case EV_BEACON_FOUND:
            printf(("EV_BEACON_FOUND"));
            break;
        case EV_BEACON_MISSED:
            printf(("EV_BEACON_MISSED"));
            break;
        case EV_BEACON_TRACKED:
            printf(("EV_BEACON_TRACKED"));
            break;
        case EV_JOINING:
            printf(("EV_JOINING"));
            break;
        case EV_JOINED:
            printf(("EV_JOINED"));
            break;
        case EV_RFU1:
            printf(("EV_RFU1"));
            break;
        case EV_JOIN_FAILED:
            printf(("EV_JOIN_FAILED"));
            break;
        case EV_REJOIN_FAILED:
            printf(("EV_REJOIN_FAILED"));
            break;
        case EV_TXCOMPLETE:
            printf(("EV_TXCOMPLETE (includes waiting for RX windows)"));
            if (LMIC.txrxFlags & TXRX_ACK)
              printf(("Received ack"));
            if (LMIC.dataLen) {
              printf(("Received "));
              printf(LMIC.dataLen);
              printf((" bytes of payload"));
            }
            // Schedule next transmission
            os_setTimedCallback(&sendjob, os_getTime()+sec2osticks(TX_INTERVAL), do_send);
            break;
        case EV_LOST_TSYNC:
            printf(("EV_LOST_TSYNC"));
            break;
        case EV_RESET:
            printf(("EV_RESET"));
            break;
        case EV_RXCOMPLETE:
            // data received in ping slot
            printf(("EV_RXCOMPLETE"));
            break;
        case EV_LINK_DEAD:
            printf(("EV_LINK_DEAD"));
            break;
        case EV_LINK_ALIVE:
            printf(("EV_LINK_ALIVE"));
            break;
         default:
            printf(("Unknown event"));
            break;
    }
}

void app_main(void)
{
    os_init();
    LMIC_reset();

    LMIC_setSession (0x1, DEVADDR, NWKSKEY, APPSKEY);

    LMIC_setupChannel(0, 868100000, DR_RANGE_MAP(DR_SF12, DR_SF7),  BAND_CENTI);      // g-band
    LMIC_setupChannel(1, 868300000, DR_RANGE_MAP(DR_SF12, DR_SF7B), BAND_CENTI);      // g-band
    LMIC_setupChannel(2, 868500000, DR_RANGE_MAP(DR_SF12, DR_SF7),  BAND_CENTI);      // g-band
    LMIC_setupChannel(3, 867100000, DR_RANGE_MAP(DR_SF12, DR_SF7),  BAND_CENTI);      // g-band
    LMIC_setupChannel(4, 867300000, DR_RANGE_MAP(DR_SF12, DR_SF7),  BAND_CENTI);      // g-band
    LMIC_setupChannel(5, 867500000, DR_RANGE_MAP(DR_SF12, DR_SF7),  BAND_CENTI);      // g-band
    LMIC_setupChannel(6, 867700000, DR_RANGE_MAP(DR_SF12, DR_SF7),  BAND_CENTI);      // g-band
    LMIC_setupChannel(7, 867900000, DR_RANGE_MAP(DR_SF12, DR_SF7),  BAND_CENTI);      // g-band
    LMIC_setupChannel(8, 868800000, DR_RANGE_MAP(DR_FSK,  DR_FSK),  BAND_MILLI);      // g2-band

    // Disable link check validation
    LMIC_setLinkCheckMode(0);

    // TTN uses SF9 for its RX2 window.
    LMIC.dn2Dr = DR_SF9;

    // Set data rate and transmit power for uplink (note: txpow seems to be ignored by the library)
    LMIC_setDrTxpow(DR_SF7,14);

    // Start job
    do_send(&sendjob);

    while(1) {
        os_runloop_once();
        vTaskDelay(10 / portTICK_PERIOD_MS);
    }
}

Console output (Sending IRQ for DIO 0 is from my debug Code to check if the IRQ is received):

I (327) lmic: Starting IO initialization
I (337) gpio: GPIO[14]| InputEn: 0| OutputEn: 1| OpenDrain: 0| Pullup: 0| Pulldown: 0| Intr:0 
I (337) gpio: GPIO[18]| InputEn: 0| OutputEn: 1| OpenDrain: 0| Pullup: 0| Pulldown: 0| Intr:0 
I (347) gpio: GPIO[26]| InputEn: 1| OutputEn: 0| OpenDrain: 0| Pullup: 0| Pulldown: 0| Intr:0 
I (357) gpio: GPIO[34]| InputEn: 1| OutputEn: 0| OpenDrain: 0| Pullup: 0| Pulldown: 0| Intr:0 
I (367) gpio: GPIO[35]| InputEn: 1| OutputEn: 0| OpenDrain: 0| Pullup: 0| Pulldown: 0| Intr:0 
I (377) lmic: Finished IO initialization
I (387) lmic: Starting SPI initialization
I (387) lmic: Finished SPI initialization
I (397) lmic: Starting initialisation of timer
I (397) lmic: Finished initalisation of timer
I (407) gpio: GPIO[14]| InputEn: 0| OutputEn: 1| OpenDrain: 0| Pullup: 0| Pulldown: 0| Intr:0 
I (407) lmic: Wait until
I (417) lmic: Done waiting until
I (417) gpio: GPIO[14]| InputEn: 1| OutputEn: 0| OpenDrain: 0| Pullup: 0| Pulldown: 0| Intr:0 
I (427) lmic: Wait until
I (517) lmic: Done waiting until
Packet queued 
Sending IRQ for DIO 0 
I (1787) lmic: Wait until
I (1787) lmic: Done waiting until

TobleMiner / lmic-esp-idf

EV_TXCOMPLETE Event missing #7