As the subject says, pairing a keyboard with a Windows 10 device results in a sharp increase in CPU utilization of the "system interrupts" process, which sticks at 20% despite no system activity and remains at this level until the system is restarted or the keyboard enters sleep mode or is disconnected (from the keyboard or from the Windows 10 machine). A number of users online have also reported that devices containing this chip are experiencing problems with Windows 10 with an actively paired Bluetooth keyboard. This includes the Surface Pro 3 and our devices, the HP Pro 608 G1. It is useful to note that devices with other chipsets and the same image of Windows 10 do not show this problem, and the affected systems with Windows 8.1 do not show this problem. It is therefore most reasonable to conclude the problem lies in the Windows 10 drivers.
All typical troubleshooting steps have been attempted (clean install of the system, multiple BIOS revisions tested, multiple driver versions tested, windows updates installed and uninstalled) to no avail. I can provide exact symptoms and attempted workarounds, or any logs requested. I am willing to get this working while the devices are with us.
I have also attempted to disable or reconfigure many of the advanced options in the device manager's advanced tab for this chipset without success. Please advise.
Update: We have traced it to power management settings. When the Intel Bluetooth device is set to not be turned off by the system to save power (there is a checkbox in Device Manager when properties is opened, in the Power Management tab), all symptoms vanish. The system, however, is then unable to enter connected standby and power draw is very high -- the network also fails to connect upon resume. But this is a lead. I hope this helps the Intel team fix this critical bug in essential bluetooth functionality.