I am trying to build an Arduino based lightsaber and for that purpose I have connected a Adafruit Mono 2.5W Class D Audio Amplifier with a small 4 Ohm 3 Watt speaker and a micro SD card module where the sound effects are stored. Everything works fine but I have an unwanted ticking sound in the audio that seems to come from Arduinos serial clock. The microSD modules clock is connected to pin 13 and I can see the LED pulsing at the same interval as I get the ticking sound. I also get the sound when I upload a sketch and the LED flashes. Does someone know how to remedy this problem?
I am using the schematics and code AlexGyvers lightsaber: https://github.com/AlexGyver/EnglishProjects/tree/master/GyverSaber