M6 SL unresponsive

I tried playing a video file that I encoded with the Batman program. I do not attribute the issue to the Batman program, as I have used it many times and never had this happen. Anyway, when I clicked on the video, the screen changed to black and none of the buttons were responsive. I attempted a hard reset and a soft reset and nothing happened. I waited a few hours and the player looked like it had turned itself off, so I tried turning it on. The updating music library started, then halfway through the screen went black again. Now nothing happens when I hold down the power button.

I'm not sure if i should use DFU tools in order to solve this problem. Any advice?

Thanks!

Well your player froze there twice, you should hold soft reset long and try again. If the player would keep freezing then update the firmware I guess. Normally if can.
Remember that you might need to hold down the soft reset button really long sometimes. Half a minute or a minute maybe.