Possibly faulty Seeeduino Stalker kit

I recently bought a Seeeduino Stalker kit, and when I try to use the Serial Monitor to read outputs, all it displays is gibberish. Even a simple Serial.println(“Hello World”) program doesn’t work. When I try something like this with my Arduino UNO, there are no problems. Is my unit faulty? What can I do to receive a new one?

Thanks, Koen

when you programming the Stalker,you have to select the 3.3v level , because the stalker run on the 3.3v different from the arduino uno(5v).
usually , the different electrical level may cause such a problem. And the other reason maybe the serial rate is set different from your codes.So, you can check this out and see what happen.