I have a 2G iPod Touch 8GB that I purchased new from Circuit City in October 2008. Lately, whenever I have plugged it into the computer, I get a "USB Device not recognized" message. I've tried other computers/ports/cables and still get the same message. The iPod charges just fine with both the wall and car charger, but won't charge when plugged into the computer. Is there anything I can do to fix it? I'd really like to upgrade to the new iOS4, plus it'd be nice to sync music again and stuff. Thanks!