Yesterday I ejected my microSDHC and loaded all of the MP3’s I wanted in the main Music folder. I also did a CHKDSK /r /x from Windows (which reported no problems). After that, everything was good. BTW, before I was not only getting “file format not supported”, I was also getting “file not found”. I’m running the latest firmware. All of my files are MP3’s ripped from CD’s with Windows 7 at the highest bitrate it offered.