All media recognized as 'unknown'

OK, 2 other possibilities:

1.  Try manually reapplyng the latest firmware–it can sometimes develop a glitch.  See the firmware sticky thread at the top of this forum.  This could fix matters.

2.  If that doesn’t fix matters, try reformatting the player under its System settings–that sometines can fix odd circumstances.  Note:  this will erase all user content on the player–copy anything you might want to save to your computer first.

Hope one or the other of the above helps!