You added the vision mode sounds to the VisionMode of Level1. This causes a problem. Since that is located at X:0 and Y:0 the sound is not moving with the player. So the longer away you are, the lower the sound is until you can’t hear it. Should’nt the AudioStreamPlayer, and maybe even the VisionMode.gd script be attached to the Player scene?
Nevermind, i did it wrong. I did not notice that you used the non 2D version of AudioStreamPlayer. My bad.
Easy mistake to make! I did a very similar thing in the prototype of Heist Meisters!