I have found a solution over answer.microsoft:
As for the "hang"
After testing 23 tries and failures to restart with the cover attached and 12
successful with no cover attached I had an a-ha moment and attached an old
Surface Type Cover 2 to the SP3. The SP3 made that nice “oh something is
I did a restart. No problem. I did it again with the older cover attached, no
Feeling brave, I removed the older cover and attached the Type Cover 3 that was
not allowing restart
I held my breath
Be still my heart, successful restart. And so far every time since this silly
cover dance it has not demonstrated this issue.
The same solution from another source "It is still the same person how wrote this":
What I did to stop the cycle (which I realize not everyone can do) is attach an
older type cover from a Surface 2 to my SP3 while it was running, got the "ah ha
new device attached" system sound, then did two or three cycles of restarts
normally. After doing that, my Type Cover 3 behaved normally (so far).
You man have to borrow a friends Type Cover 2 to do this or see if there is a
Microsoft or other store nearby that will let you use their display to do this.
I got back from the MS store. Their lead tech fixed it. Apparently there were several firmware updates that didn't take (Remember that the latest "firmware update" actually has several individual firmware patches in it). I tried to watch the commands that he executed to reset the windows update, it wasn't the normal DISM commands that I knew. He went directory deleting, invoked windows update from the command line with extra switches, removed a couple devices from device manager, reinstalled them, etc..
He went fast. It reminded me of myself 10 years ago fixing Windows servers. The kicker was he cleaned his tracks when he was done, so I couldn't go back in history to see what he did!!! I tried to press him on the commands and such, but he wouldn't give up the information. Most of the stuff I could see (he did well to turn the screen away from me, so it was really difficult to see everything) was normal stuff, but the secret sauce was a particular directory and it's contents he deleted, and the command line switch to kick off windows update.
So when. You put the original Type cover back on after the old type cover does it also make the new device sound?
Think about what's happening here... maybe a different driver but not necessarily either way perhaps some piece of software was corrupted and got replaced/refreshed by the keyboard swap or some registry entries got modified/added/replaced.
It seems to be another manifestation of the same problem that plagues Surface Pro's... (haven't noticed it with Surface RTs/2s)
Something gets corrupted in the configuration (software or settings) either as a result of changing a device or performing regular updates and if your lucky you can do something to resolve it otherwise you end up doing a Refresh.
I switched a monitor from a DVI connection to a DisplayPort connection then back to DVI at that point it wouldn't display anything on the monitor anymore until I did a Refresh. I have seen numerous posts about people suddenly having problems after Windows Updates gone wrong, then maybe you remove them and reinstall to fix or end up doing the hail Mary REFRESH.
Maybe there's an issue with committing changes or flushing changes to disk before restarting or a drive firmware problem but there is a commonality to all of this with something. Too frequent to be coincidental or just random space particles but it doesn't seem limited to any one subsystem, module, or configuration setting.