MKR1310 keeps restarting at sending

MKR1310, LoRa receiving works great.
Trying the simple DumbModemLoRaSender script makes my MKR1310 restarting.
Again, receiving works good, sending is a problem.
Any suggestions?
Regards
J

Also tried with lower baudrate btw.
#include <SPI.h>
#include <LoRa.h>

int counter = 0;

void setup() {
Serial.begin(115200);
while (!Serial);

Serial.println("LoRa Sender");

if (!LoRa.begin(868E6)) {
Serial.println("Starting LoRa failed!");
while (1);
}
}

void loop() {
Serial.print("Sending packet: ");
Serial.println(counter);

// send packet
LoRa.beginPacket();
LoRa.print("hello ");
LoRa.print(counter);
LoRa.endPacket();

counter++;

delay(5000);
}

Dump register:

14:55:30.771 -> LoRa Dump Registers
14:55:31.212 -> 0x0: 0x93
14:55:31.212 -> 0x1: 0x81
14:55:31.212 -> 0x2: 0x1A
14:55:31.212 -> 0x3: 0xB
14:55:31.212 -> 0x4: 0x0
14:55:31.212 -> 0x5: 0x52
14:55:31.212 -> 0x6: 0xE4
14:55:31.212 -> 0x7: 0xC0
14:55:31.212 -> 0x8: 0x0
14:55:31.212 -> 0x9: 0x8F
14:55:31.212 -> 0xA: 0x9
14:55:31.212 -> 0xB: 0x2B
14:55:31.212 -> 0xC: 0x23
14:55:31.212 -> 0xD: 0x1
14:55:31.212 -> 0xE: 0x0
14:55:31.212 -> 0xF: 0x0
14:55:31.212 -> 0x10: 0x0
14:55:31.212 -> 0x11: 0x0
14:55:31.212 -> 0x12: 0x0
14:55:31.212 -> 0x13: 0x0
14:55:31.212 -> 0x14: 0x0
14:55:31.212 -> 0x15: 0x0
14:55:31.212 -> 0x16: 0x0
14:55:31.212 -> 0x17: 0x0
14:55:31.212 -> 0x18: 0x10
14:55:31.212 -> 0x19: 0x0
14:55:31.212 -> 0x1A: 0x0
14:55:31.212 -> 0x1B: 0x0
14:55:31.212 -> 0x1C: 0x0
14:55:31.212 -> 0x1D: 0x72
14:55:31.212 -> 0x1E: 0x70
14:55:31.212 -> 0x1F: 0x64
14:55:31.212 -> 0x20: 0x0
14:55:31.212 -> 0x21: 0x8
14:55:31.212 -> 0x22: 0x1
14:55:31.212 -> 0x23: 0xFF
14:55:31.246 -> 0x24: 0x0
14:55:31.246 -> 0x25: 0x0
14:55:31.246 -> 0x26: 0x4
14:55:31.246 -> 0x27: 0x0
14:55:31.246 -> 0x28: 0x0
14:55:31.246 -> 0x29: 0x0
14:55:31.246 -> 0x2A: 0x0
14:55:31.246 -> 0x2B: 0x0
14:55:31.246 -> 0x2C: 0x0
14:55:31.246 -> 0x2D: 0x50
14:55:31.246 -> 0x2E: 0x14
14:55:31.246 -> 0x2F: 0x45
14:55:31.246 -> 0x30: 0x55
14:55:31.246 -> 0x31: 0xC3
14:55:31.246 -> 0x32: 0x5
14:55:31.246 -> 0x33: 0x27
14:55:31.246 -> 0x34: 0x1C
14:55:31.246 -> 0x35: 0xA
14:55:31.246 -> 0x36: 0x3
14:55:31.246 -> 0x37: 0xA
14:55:31.246 -> 0x38: 0x42
14:55:31.246 -> 0x39: 0x12
14:55:31.246 -> 0x3A: 0x49
14:55:31.246 -> 0x3B: 0x1D
14:55:31.246 -> 0x3C: 0x0
14:55:31.246 -> 0x3D: 0xAF
14:55:31.246 -> 0x3E: 0x0
14:55:31.246 -> 0x3F: 0x0
14:55:31.246 -> 0x40: 0x0
14:55:31.246 -> 0x41: 0x0
14:55:31.246 -> 0x42: 0x12
14:55:31.246 -> 0x43: 0x24
14:55:31.246 -> 0x44: 0x2D
14:55:31.246 -> 0x45: 0x0
14:55:31.246 -> 0x46: 0x3
14:55:31.246 -> 0x47: 0x0
14:55:31.246 -> 0x48: 0x4
14:55:31.246 -> 0x49: 0x23
14:55:31.246 -> 0x4A: 0x0
14:55:31.246 -> 0x4B: 0x9
14:55:31.246 -> 0x4C: 0x5
14:55:31.246 -> 0x4D: 0x84
14:55:31.246 -> 0x4E: 0x32
14:55:31.246 -> 0x4F: 0x2B
14:55:31.246 -> 0x50: 0x14
14:55:31.246 -> 0x51: 0x0
14:55:31.246 -> 0x52: 0x0
14:55:31.246 -> 0x53: 0x10
14:55:31.246 -> 0x54: 0x0
14:55:31.246 -> 0x55: 0x0
14:55:31.246 -> 0x56: 0x0
14:55:31.246 -> 0x57: 0xF
14:55:31.246 -> 0x58: 0xE0
14:55:31.246 -> 0x59: 0x0
14:55:31.246 -> 0x5A: 0xC
14:55:31.246 -> 0x5B: 0x0
14:55:31.246 -> 0x5C: 0x7
14:55:31.246 -> 0x5D: 0x0
14:55:31.246 -> 0x5E: 0x5C
14:55:31.246 -> 0x5F: 0x78
14:55:31.246 -> 0x60: 0x0
14:55:31.246 -> 0x61: 0x1C
14:55:31.246 -> 0x62: 0xE
14:55:31.246 -> 0x63: 0x5B
14:55:31.246 -> 0x64: 0xCC
14:55:31.246 -> 0x65: 0x0
14:55:31.246 -> 0x66: 0x1
14:55:31.246 -> 0x67: 0x50
14:55:31.246 -> 0x68: 0x0
14:55:31.246 -> 0x69: 0x0
14:55:31.246 -> 0x6A: 0x0
14:55:31.246 -> 0x6B: 0x0
14:55:31.246 -> 0x6C: 0x0
14:55:31.246 -> 0x6D: 0x0
14:55:31.246 -> 0x6E: 0x0
14:55:31.246 -> 0x6F: 0xB
14:55:31.246 -> 0x70: 0xD0
14:55:31.246 -> 0x71: 0x0
14:55:31.246 -> 0x72: 0x13
14:55:31.246 -> 0x73: 0x0
14:55:31.246 -> 0x74: 0x0
14:55:31.246 -> 0x75: 0x0
14:55:31.246 -> 0x76: 0x0
14:55:31.246 -> 0x77: 0x0
14:55:31.246 -> 0x78: 0x0
14:55:31.246 -> 0x79: 0x0
14:55:31.246 -> 0x7A: 0x0
14:55:31.246 -> 0x7B: 0x0
14:55:31.246 -> 0x7C: 0x0
14:55:31.246 -> 0x7D: 0x0
14:55:31.246 -> 0x7E: 0x0
14:55:31.246 -> 0x7F: 0x0

pinMode(LORA_BOOT0, OUTPUT);
pinMode(LORA_RESET, OUTPUT);
In setup() seems to do the trick.