My Turbo 2 shuts off without any warning even when it still shows a high percentage of battery remaining. It started doing this a few weeks ago when it showed 20%, and its gradually gotten worse. Today it shut down at 44%. It usually will start again with the power button, and shows the battery percentage the same as when it shut down. Sometimes it will not even finish the start up sequence, just shuts down part way through. If I connect to a charger it will always fully start, showing the percentage as before, and will gradually charge. I tried to "calibrate" the battery through 3 complete discharges and recharges. It usually shuts off before draining below 30%, and doesn't seem to calibrate. Still shuts down at a high percentage. Did a hard reset of the device today, and it shut down two hours later at 44% after I got it going with just the factory installed apps, minus some bloat. Did not help at all.