I paired my Apple Bluetooth keyboard with my Macbook Retina running 10.8.3 today, and noticed that my fan starting running really loudly.
Opening Activity Monitor, it showed that a task, "SystemUIServer" was using between 80 and 90% of my CPU. Distnoted was also up there, using 10%. 60+ GB of swapfiles in private/var/vm were created, which was a huge size in comparison to my 250gb hard drive that only had 90gb free prior. (These were removed upon a restart)
Looking at my menubar (a google search showed that SystemUIServer often has to do with menubar icons, I saw that my wifi icon was glitching a bit, frequently flashing. Clicking the icon, I saw that its status kept switching between "Wifi: On" and "Wifi: Searching", about five times per second.
screenvideo: http://f.cl.ly/items/3o0d1u2j0x2P1l33203Q/screenrecord.mov
Turning Wifi off resulted in everything going back to normal. (With the exception of no wifi connection anymore)
Doing some debugging, I found that turning bluetooth off and restarting the computer fixed the problem, up until I turned bluetooth back on, in which case the symptoms would immediately begin again.
Further debugging leads me to believe that it is specifically my bluetooth keyboard (I also use a magic mouse) causing the problems. Turning bluetooth on but remaining unconnected with the keyboard does not cause any problems. Connecting to the keyboard immediately starts the symtom, and disconnecting immediately relieves the symptoms.
I had it connected with just the magicmouse, after about half an hour the problem started happening again…
Sorry for the wall of text, I just wanted to document everything about the situation. It may also be worth noting that I also started using Time Machine with an external hard drive right before this started, but I don't think it's related.
Any ideas? I'd like to be able to use my bluetooth keyboard…
Best Answer
Bluetooth and WiFi do use the same 2.4GHz1 frequency bands (as do many other things), so they could interfere relatively easily. It also doesn't help that there are a lot of networks in your area. However, I find it highly unlikely that the interference would cause you to lose your connection, given that the video shows a full 4 bars when you are connected.
Personally, I would suspect a hardware issue in this case. The Bluetooth and WiFi connections are most likely controlled by the same chip in your computer, so it may be malfunctioning only if both of its services are being used. Try reproducing the issue on someone else's wireless network, and take it in to an Apple Store if you can. If you cannot reproduce it on someone else's network, it may be that your router is picky with its connections, or something else completely.
1 802.11n does allow using a 5GHz band instead, so you could try that if your router and computer support it. It isn't very commonly used yet, so there is typically little interference there.