The problem occurs sometimes, when you wan to shut the device down. To diagnose if the device is in a fake shutdown status, just press navigation buttons. If you see the green light, then you'll know it was not able to shut down properly. Simply reset via stylus, and shut down again. Would work 99% of time.
I've come across this just before a 2.5 hour train trip. I've plugged in the dr1000s to laptop. Shut down the dr1000s, and ordered a shutdown -h +180 to ubuntu (shut down after 3 hours) and went to bed. Normally, this charges the device, cuts the power, and you pick it up and get on the train with your coffee.
In my case, I ended up with a completely drained device and watching the scenery from a train window for 2.5 hours. I've later found out how it happens
In other times, keeping the device off, does not affect battery at all (or it is not noticable )
Best
Seref