Hi I have had these googles for a little bit now and when I first got them the fan for the lens defogger were noisy sometimes. I just thought it was the colder temps outside and figured it would go away in the spring. I haven’t had much time fly since busy with other things. It’s been warmer here now so I been using the googles a lot and and the fan is still noisy. After about 10min or so of flight time there is another noise that sounds like screeching brakes from inside the case. If figure this is a cpu fan of some sort since it is still there when I turn fan off with button. The lens defogger fan sounds like it is rubbing on something like when you put a baseball card on a bike tire and it hits the spooks.