I love the temps & ease of install of the Thermalright Peerless Assassin CPU cooler I put in my wife’s new build, but I don’t love the subtle but noticeable fan whine. I’ve double checked they’re mounted in the right direction (no arrows on the fans, tsk), seems fine. May try shifting them a bit and if that doesn’t work, actually buy some decent fans - this cooler is very highly rated but also cheap as chips so I’m probably being a little unfair to expect Noctua / BeQuiet sound levels I suppose