I wonder -- if it does have something to do with the wifi -- if this is somehow related to the wireless dropping issue a lot of Macbook Pro users experience. I was having serious issues with my MBP dropping internet and finally bought the base station. No dropping problems with it, but perhaps the base station has to work harder to maintain a connection with my still technically broken MBP. (If I take the MBP into the real world, I will continue to have internet connection problems). Anyway, I'm not technically savvy at all, so this may be a totally misguided suggestion. I have the whirring problem while _not_ dowloading large files.
I just got myself an AirPort Extreme (5th gen) today, and am experiencing the same problem.
After I heard this noise, I found out that it's exactly the same noise my Early 2011 MacBook Pro is making when I am generating heavy Wi-Fi traffic.
Same goes for the MacBook Pro's at my work. It's not the power supply or what so ever, it's probably the Wi-Fi module or internal card bus which is handling all the I/O within the device.
After I found out that MacBooks I own and manage are making the same noise, I am pretty sure it is normal behavior, and decided not to return it to the store I bought it from.
P.S. My apologies for bumping this old topic
Got the same situation. I have noticed that it scratches only when I download or upload something big (as the speed of the Internet connection becomes high). When nothing wireless is connected, there is no noise at all.
Actually, this noise doesn't annoy me. But I worry about the problems with my device.
Does anybody have any explanations from Apple?
Old thread but I still have a buzzy Airport Extreme
Just want to confirm it's related to the data volume delivered. When my Mac shows 100 - 200KB throughput, it's very quiet (but stil audible). If I show 2MB/s throughput, it gets loud. The more data it delivers, the louder it gets. It's as if the bits and bytes are actually rushing through...
This is really old, but i'll put my two cent in on how i got mine to stop making the buzzing sound:
I had this issue after moving. The buzzing sound happened during data traffic, most noticable when doing a large DL (can't hear during UL) while testing on speedtest.net
This had never occured to me before - i've had the airport for about a year with no noise. then i realized that (as everyone said) that when you are directly connected to the router via an ethernet cord, it makes no noise (and it doesn't)
so the fix? just plug an ethernet cord to one of the ports on the back even if you are going to only use it as a wireless device... it seem's to rid of the buzzing sound altogether.
I have a A1301 (3rd generation) and since I started to use a MBAir (2013) I noticed the AE and power supply both bussing madly during large data transfers across my internal network. I did a test and switched from the 5GHz to the 2.4GHz wireless and the repeated the same tests and the router remained silent.
On the 5GHz I get real download spead of about 20MB/sec and on the 2.4GHz only about 6-8MB/sec.
So it must be the power consumption on the wireless chip.