Wierd printing on hight bps

void setup()
{
// Open serial communications and wait for port to open:
Serial.begin(57600);
Serial.println("Goodnight moon!");
}
void loop(){
}

This is my code and in Serial i get "s²ø" and if i restart with the button on arduino i get "s²øq³ù" ex.
If i Serial.begin(9600) everything is fine, can anyone explain me what's happening?

http://arduino.cc/en/Reference/SoftwareSerial, I got this from this example

???

#include <SoftwareSerial.h>

SoftwareSerial mySerial(10, 11); // RX, TX

void setup()  
{
  // Open serial communications and wait for port to open:
  Serial.begin(57600);
  while (!Serial) {
    ; // wait for serial port to connect. Needed for Leonardo only
  }


  Serial.println("Goodnight moon!");

  // set the data rate for the SoftwareSerial port
  mySerial.begin(4800);
  mySerial.println("Hello, world?");
}

void loop() // run over and over
{
  if (mySerial.available())
    Serial.write(mySerial.read());
  if (Serial.available())
    mySerial.write(Serial.read());
}

serial monitor, select the proper speed

Thank you :slight_smile: