I've searched numerous forums and tried tons of different things, but I cannot solve my problem. I have an iPhone 4 that used to be my primary phone, but now I'd like to use it as an iPod since I have an iPhone 5 now. However, no music will sync to the iPhone 4. I usually sync selected playlists/albums/etc., but for some reason all the sudden no songs will sync. When I select the music tab under the Devices section in iTunes, all the songs are there, but they are grayed out. Same thing happens when I look for songs on the iPhone 4 itself. I've tried unchecking "Sync Music" then reselecting it, but to no avail. The phone is not jailbroken or hacked in anyway. Any ideas? I may have to do a full restore, but I was hoping to avoid that.