Tablet won't shut down completely after Windows 10 upgrade

[RWD]

I upgraded my Lenovo Thinkpad Tablet 2 to Win 10 a few weeks ago. Since then, it won't fully power down 9 times out of 10. I close all apps, and select shut down from the power menu, and it appears to go through the shut down process, but it stays powered - the haptic feedback Windows button buzzes when pressed. If I don't plug in the charger it will kill the battery.

The only way to power it back on is to hold down the power button for 15 seconds.

Any ideas?

 

[realwarder]

Have you checked for BIOS updates? power off is low level.