On the senior video player, the square dance that used to be able to play why now prompts the format is not supported?

Previously can play, now can not,

Memory card

Also out of the problem, met too short music files can be played, larger files prompted by the format is not correct, change the playback software can not be, and finally replace the memory card, and then can be played again!

This is the first time I've seen this on a PC, and I'm sure it's a good idea to try it on a different card!