Currently Being ModeratedAug 26, 2012 7:59 AM (in response to h.sabrey)
bluetooth connection is incredibly unreliable/intermittent when in Windows (I run Windows 7 64-bit and Boot Camp 4.0, and got both devices connected without any trouble via Bluetooth).
After much testing, I have found the cause of lagging/jumpiness on the Bluetooth Magic Mouse and Magic TrackPad in Boot Camp.
Hopefully this will help others:
The drivers for the Broadcom 802.11n Wireless Adapter have a setting called "Bluetooth Collaboration" that is Disabled by default. Enabling this option removes the problem instantly.
My Magic Trackpad now works flawlessly, even if I stand 6 metres from the machine. It now works just as well as under Mac OS. The setting can be found under:
Control Panel > Device Manager > Network Adapters > Broadcom 802.11n Network Adapter (right click and choose "Properties".
Under the "Advanced" tab, highlight the setting named "Bluetooth Collaboration", then change it to Enable. Then click OK.
I narrowed the problem down to the wireless card by disabling ALL startup services and processes for Windows, then re-enabling one by one.
As soon as I enabled the Windows Wireless Service, the problem came back.
Similarly, disabling the Wireless Card inside the Network and Sharing Center (or Device Manager) removes the problem.
This led me to believe it must be a driver issue with the wireless card, since the problem didn't occur with the Magic TrackPad under Mac OS, or on my mother's Windows 7 64-bit computer.
So when I went into the Driver Properties to check for an update, I found this setting about Bluetooth Collaboration.
All Apple notebooks use the Broadcom card (and have done for years), so this driver is installed for almost anybody using Boot Camp on an Apple notebook. I'd assume this problem would affect anybody using Boot Camp + wifi + a Bluetooth device.Mac Pro, Windows 8 Preview x64 3.2GHz