I have a problem with my Vivotab Smart, since the Windows 8.1 update, more so the Feb updates every device I connect to the micro USB port (via otg cable) is an unknown device. I have just completed a RMA with Asus but I was wondering if anyone else has these problems? I know there was some issues with the updates as they updated the USB stack but even after a Windows reset/reinstall I cannot connect any device. Previously I could reinstall windows 8 and USB worked for a bit. But now apart from charging nothing shows up, all devices code 43.