Ipod skips songs and / or freezes, won't play any song
Listening to my ipod I skipped to next track, but no sound came. Looking at display I noticed that the ipod had skipped about twenty tracks. Tried going back to track I wanted to play but ipod wouldn't play it - time display stuck at 0.00 for a few mins then skipped to next track, same problem. Went to completely different track - same problem.
Checked on itunes - all songs played fine, both those listed under my home hard drive, and those listed under the ipod's drive on itunes.
Resynched ipod - same problem - initially one or two songs would play, but when trying to play the specific track I first tried, it would skip through the next twenty or so tracks then stop playing anything.
Tried soft reset - same problem.
Tried restoring to factory settings - same problem.
Took to apple store genius bar - they made no attempt to work out what was going wrong, just replaced ipod as it was still under warranty. Got home and resynched all songs - same problem!
This suggests it is a problem with the song files, but I don't understand why they play fine on itunes. Also, the file type (mp3), bit rate, sample rate, file size, etc is exactly the same in both locations.
Have tried all troubleshooting tips on this site, and all software is latest version.
Any ideas?
iPod classic 160GB (Late 2009), Windows Vista