Strange behavior by pressing BTN

Hi,

I've tried to write a program for the Espruino.
I'm new to Espruino and Java, so it is possible that I'm asking stupid questions ;)

I have a Espruino Classic with a ILI9341 connected.
If I run the program while the PC is connected to the board, It works fine.
But when I change (In communications - Save on Send) Direct To Flash, the preset variable "HomeScore" shows "2" on the display, and when pressing the BTN, It goes up with 2 counts or sometimes 3 counts.

Is this a known error, or do I something wrong?

Regards,
Peter

B2.set(); // light on
 var HomeScore = 0;

SPI1.setup({sck:B3, miso:B4, mosi:B5, baud: 1000000});
var g = require("ILI9341").connect(SPI1, B6, B8, B7, function() {
  
  g.clear();
  g.setRotation(3);
  
  g.setFontVector(30);
  g.setColor(0,255,0);
  g.drawString("Home",5,50);
  g.setFontVector(45);
  g.setColor(255,255,255);
  g.drawString(HomeScore,40,85);
  
});

var LocHome = 0;
function HomeUp() {
  g.setColor(0,0,0);
  g.setFontVector(45);
  g.drawString(HomeScore,25+LocHome,85);
  if (HomeScore<10) LocHome=15;
  if (HomeScore>8) LocHome=0;
  HomeScore = (HomeScore+1);
  g.setColor(255,255,255);
  g.drawString(HomeScore,25+LocHome,85);
}

setWatch(HomeUp, BTN, {repeat: true, edge:'falling'});