i cut your main program flow out and put in prints:
float start, runtime;
void setup() {
size(1200,100, P3D);
start = millis();
}
int loop = 0;
void draw() {
loop++;
runtime = millis() - start;
if (mouseX > 1100) {
println(loop+" > 1100 "+(int)random(3));
} else if ((mouseX < 1100) && (runtime > 5000)) {
println(loop+" < 1100 && runtime > 5000 "+(int)random(3));
} else {
println(loop+" walking");
}
if (runtime >= 20000) {
start = millis();
println(loop+" runtime >= 20000");
}
}
now you see what you are doing to the computers audio player!