Another radion question, this time.....fans

[Coralgurl]

Im not sure if it's because I've been away and just noticing, but the fans on my radions are really loud. At first I thought my power heads were misaligned so I checked them, then checked the return pump and finally figured its the fans.

It's actually quite annoying. Is this normal? I don't remember them being this loud before. Are they louder depending on settings throughout the day due to light intensity?