Sounds like you either have a bad hard drive or some of the song files are corrupted.Have you gone into the "Emergency Connection" mode to reformat the player? Rest the player; if it's a 20gb stick a paper clip in the reset hole, on a 5 or 6gb remove and replace the battery. Then connect the player to the PC. Hold the enter button down when you turn it on, it should come on and read "emergency connection" at the top within a black band.
You must go to the iriver.com web site and download the firmware updater for your player. Her is the link; http://www.iriveramerica.com/support/hd/. Then select either the 5-6 or 20gb firmware. Run the firmware program while the player is in the "Emergency Connection" mode. You can also get the firmware upgrade info from iriver. That should solve your problems and in addition you will be getting the latest firmware.
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