I have occasional similar problems
Maybe once a week so far. It displays the loading symbol and stays there. I try to turn it off, but it won't turn off. After 2 - 5 tries it does shut off, and after that, it works fine. I normally shut the device off when I'm done with it, if that makes a difference.
To me, it sounds like a firmware issue, though I have no way of knowing at this point.
Clearly, this is not an issue that is unique to me or my operation of my unit since this is an issue with several people. I wonder if Sony will step up and do something?