USB drive only play intermittently...HELP

I have a WD Element 2TB hard drive connects to the WD Live Plus.  I played a WMV file and it works fine.  I stopped and play another WMV file (High Def) only to see the stupid blue circle.  So I tried to play the previous WMV file that was played fine before.  It did not play, stupid blue circle again.  I check the codecs on both files and they are VC-1 and WMV9 which are supported by WD Live.   Reboot will help but problem still persist.  I am so frustrated and about to  bring it back to Best Buy.  Any suggestion?

4H and 4I in the FAQs

So is there a known cause for this problem and permanent fix?  Rebooting or resetting is too much hassle.

4H and 4I in the FAQs