unless you're seeing mucus its not definitely ri my babies whisper sweet nothings in my ear and it sounds like a whistle all of my babies are in good health i thought it was weird the first time i heard it asked the vet about it when i took them for their physical exam and he told me what signs to look for ie mucus mouth rot in really bad cases so far healthy and happy snakes just whistle when they breath but not generalised for all of my babies don't whistle just 2 of them