I have a Mac Pro 2009 that is unable to reliably work with the new magic mouse. The connection is spotty and either drops or there is significant lag on screen. The mouse is 3 ft, 7 inches from the front of the computer case so the distance should not be causing the problem. I've noticed that previous threads have discussed wiring problems with the BT radio, but those appear to be on earlier Pro models. I opened the case and I'm unable to find the BT receiver to even verify if the wiring is correct. If I use the Magic Mouse under my desk about 2 feet from the case, it does work reliably, but the ergonomics of that setup interferes with my productivity. I'd prefer not to purchase an external BT dongle. I am using 10.6.1 and all known updates are installed. I do not have Airport. Any suggestions welcome. thanks.