Hi there,
There's an active discussion over on the Surface forums regarding the 9/9/2014 firmware update causing Bluetooth issues, primarily w/ the K810 (but I'd imagine this could be w/ other BT keyboards as well).
http://www.surfaceforums.net/threads/logitech-k810-keyboard-and-9-9-14-firmware-update.11391/
Prior to this firmware update I was able to use my Logitech K810 without issue with my Surface Pro 3. However, now it just goes into a connect/reconnect loop. I'll see "driver error" briefly. And then it'll try connecting again.
Looking into the event log for Administrative events, I see this:
Bluetooth HID device either went out of range or became unresponsive.
I also see another event within seconds that says this:
Metadata staging failed, result={66F5F5A4-2104-53C0-BCDF-9DD1AF9AE33F} for container '0x80070490'
All of this appears to be an issue with the driver and/or firmware.
Furthermore, the keyboard works when pairing (typing in the keycode), but immediately after pairing it fails. So there is certainly something wrong and I don't believe it's the keyboard.
Anyone?
-Steve