Do a hard reset Hold enter key and on/off button on top at the same time for 1 minute and release. Now try and turn on. If it does not do it again. This will work
Thanks from me, too. My new M6 just wouldn't turn on after I loaded some songs on it the first time. On/off + enter for over a minute then doing it again for a bit did the trick.
The reason this happens is because the Enter Key, when held down, turns off the miniplayer after twenty seconds. Unfortunately, it doesn't solve my problem, but by playing with it the last three or four days, I have noticed this feature with the latest firmware.