Did you do this:
If you have windows 8.1 there are problems with 8.1 and the latest iTunes
I am having the same problem & I have uninstalled & reinstalled iTunes. I've also:
- Turning off/back on my iPod
- Wi-Fi & USB sync
- I have Windows 8.....not 8.1
- this, from a community specialist (matt00)
First, connect your device and choose the "Music" tab. Next, uncheck the "Sync Music" checkbox, and apply the changes (so there is ultimately no music syncing to your iPhone).
Once you have done that, recheck the "Sync Music" checkbox, and apply the changes once more. This will instruct iTunes to completely remove all music from your iPhone, and then copy the files once more. If you have a large amount of music, this initial sync may take a while.
I didn't have any problems syncing my iPod Touch 5 Gen, UNTIL I downloaded the latest ioS update (7.0.4). I'm also having problems with my Podcast app (I know...post this to a different board). I would download new podcasts, only to have them disappear once I'm not connected to Wifi. I really don't want to do a system restore b/c I'm scared I will lose things that "should have" been backed up.