I have all of the hardware that should cause this problem, but I'm not having any issues like those described. I was just browsing through the support issues and thought I might be able to offer some info or assistance.
There are any number of reasons that connecting the Cinema Display (I use a 27") to a MacBook could cause issues of this sort. Let me just run through the ones that I can think of off the top of my head… No particular order.
- Bluetooth and WiFi g/b share the 2.4 gigahertz frequency. They also share this frequency with a large number of wireless devices around the home, such as baby monitors, cordless phones, wireless cameras, and the like.
- Interference from microwave ovens.
- Signal strength can be attenuated by grounded metal objects in the path of the signal, such as with the closed lid of a unibody MacBook or the back of the Cinema Display.
- The Cinema Display uses USB for sound and as a USB hub. This may be causing latency problems if the network hardware or the bluetooth hardware in the MacBook are internally connected to the same USB bus as the monitor. I do not know this to be the case in MacBooks, but I have seen this implementation in other desktops and laptops.
- Software issues and network connectivity problems can both cause mouse latency. What happens is that a service crashes and while launchd is busy re-launching the service, other services can stack up communication buffers. The network issue is similar, but tends to have longer periods, like .5, 1, and 2 minutes. The problem is that a foreground app is waiting in vain for some data via the network interface and the network interface is busy doing nothing while a connection times out. More often this is a problem with PC's than Macs, but it happens.
There are many more issues that could cause these symptoms. Basically, when wireless-anything is involved, you have to get back to the basics for radio transmission. First, establish line-of-sight between the two devices, then check for signal strength and interference problems by moving the devices as close together as possible. Second, eliminate interference by unplugging any other cordless devices in the home or office. If those actions do not solve the problem, then the issue may be caused by other activities being performed by the device at either end of the wireless connection. Check for errors on the System Console.
In this case, the problem seems to be interference between the WiFi and Bluetooth radios. If you do not have the option of moving to a 5ghz-only WiFi network, or if you feel that the throughput of dual-channel WiFi is worth some work, then try reducing the power of the WiFi radios, first in the MacBook, then in the WiFi router. It is possible that the Bluetooth signal is just getting drowned out by the more powerful WiFi signal. You would be amazed how many people run their Wifi radios at maximum power when the router is across the room or in the next room. Not only is this not necessary, it causes interference issues and presents a security issue. After all, to hack your home network, one must first be able to connect to it. You don't really need to surf from your neighbors back yard…;-)