If my TPT has less than 20% charge, I notice two problems that seem related, as they only happen together:
1 - Quick-pressing the power button once will NOT wake the tablet, on the 2nd press the lock screen will flash, but not stay on. On the 3rd press, nothing happens, but the 4th press will cause lock screen to flash again. Usually on the 5th attempt, I can get the lock screen to stay on, where I can unlock the tablet. Less frequently, it takes another pair or two of tries.
2 - I cannot get it to keep the display on for very long after successfully unlocking it. The screen stays on anywhere between 5 and 15 seconds, and then I have to attempt to unlock again if I want to use it for another 10 seconds.
I noticed this problem started sometime last week (possibly as result of an OTA from last week). I let the tablet sleeping while charging until it has about 30% charge, and then I can use it normally again. I'm running build A310_02_0024_0065_US.