HT1363: Putting iPod into Disk ModeLearn about Putting iPod into Disk Mode
Currently Being ModeratedNov 13, 2012 6:08 AM (in response to Peteypan)
It could be an indication or a damaged or dying hard drive. I would recommend doing a disk diagnostic on the iPod's HD using the instructions given by turingtest2 in this older thread. He also covers what the resulting numbers indicate.
If necessary, post the resultings numbers and we can verify what the next steps to take.