I've tried over and over and even turned the sound effects to max on my computer, but I still haven't heard any whistling.
I must confess that I'm glad I don't. I think it would creep me out. So, me personally, I'm fine with just the windchimes.
I do believe you are hearing it though. Maybe you need to be at a certain level of the game before you can hear it.
Your not nuts so just have fun with all the little things that make VV2 what it is.
Linda