Answer to: Mac Pro Late 2013: Anything that can be done about coil whine?I discovered that this whine is mostly related to having an Ethernet cable plugged in. Then I noticed that the whine is the sound of data flowing through that port. Send a huge file and it is loud and continuous. Stop all connections(including others on that network) and it is just an intermittent buzz of the network chattering. I took my machine into the apple store shortly after buying it. I don't think they actually heard the whine and I hadn't yet connected it to having an ethernet cable plugged in. They replaced the power board or some such. Didn't fix anything. Still whine all this time later.
Answer to: Mac Pro Late 2013: Anything that can be done about coil whine?Not quite a solution but I have noticed that if I twist the case when it starts that it will stop. Basically the case can move maybe a quarter mm and this seems to stop it for a while. I almost wonder if the thing is resonating with the case or something? This does not fix it but it does stop it for a while. When I twist it I also am pressing on the interior so that could also be part of this "fix" Oh I took mine in during the first week and they replaced the power something. Didn't fix it. The problem was that their shop was too noisy to hear it.