Album Art and Star Ratings on External Memory

I’ve been having a problem syncing the album art and star ratings when using the external memory.  If I sync to the internal memory, everything is fine.  If I sync to the external memory, some album art is lost and star ratings never transfer.  Why would this work for the internal memory but not the external memory.  This problem happens whether I use WMP (v 12) or drag the files using windows explorer with the sansa mp3 player connected to the computer.  I toggled between the different USB modes on the my sansa, and neither makes a difference.  I have a sansa e260 v2 with the latest firmware (v03.01.16A).  Internal memory is 4 GB.  For external memory, I’m using an 8 GB Micro SD.  This problem is driving me crazy.  Any help or suggestions are appreciated.

<Edit> I did find one possible solution.  If I take the micro SD card out of my sansa and plug it directly into my computer, transfer the files to it using windows explorer, then eject the micro SD card and insert it into my sansa, album art and star ratings are maintained.  Why this works whereas linking the sansa to the computer doesn’t makes no sense to me.  It seems the sansa itself creates a problem.