you need to select and calibrate a microphone in the settings (using the "Microphone Calibration" button - which tells you to use 4 different levels of volume through your mic for 5 seconds each). it should automatically bring you to that screen on your first boot, but i might've messed that up :/
after that, the "intensity" of the waves is dependent on the volume that comes through your mic. if no red waves come out of your character upon loading a room, try pressing R to reset the level a few times - it's a bug i didn't manage to hammer out in time
thank you for trying it out! yeah, the microphone sometimes isn't detected when switching rooms, it's a stubborn problem that i couldn't quite figure out in time. thanks for the review :]
as for the waves? each wavefront is a GPUParticles2D node which uses a particle shader to disperse them in a "cone" shape. if you're curious i can share the code! if you meant sound effects as in noises those are just fmodeventemitters
