iPhone randomly skips music tracks? You're not alone.
A lot of users do find themselves at this uncomfortable spot. That too, when it skips over those favorite tracks that you specifically want to listen. This isn't new, though. These issues have been there since iOS 4 (or probably even older). And there are a lot of reasons why this happens.
This is not supposedly an exhaustive list of troubleshooting tips but I've tried to fit everything in here. As an avid listener, I really know how bad it is when the iPhone just randomly skips over a few songs.
So let's try to fix this thing.
1. Bad tracks?
This is a bummer. Bad or corrupt files aren't going to be played. And there isn't going to be an error message either although that doesn't make any sense. If you've not purchased the track from iTunes (which means if you've purchased from elsewhere or just plain downloaded), you should probably make sure the file isn't corrupt or unsupported. Make sure the file is in the right library of your iTunes and plays on the computer. May be check if the file plays in any other iOS devices (iPod, iPad etc.) and then come back to adding it on the iPhone. If it doesn't play on other iDevices too, the problem could be that of the file or the sync process.
If you can get alternative versions of the same track, try adding them to the library and syncing it. If the stuff works, you've cleared the error.
If not, proceed further.
2. Sync Errors
Did something interrupt the sync? Usually, when you try to sync, it is best to let iTunes and iPhone be without tinkering with either. After all, sync (if you do it frequently) takes less than a few minutes. In case sync was interrupted (even if all Music files had been synced), there's a strong chance that the data wasn't written properly to the iPhone.
Make new libraries out of your music tracks and then sync them again. This might help.
3. Wrong Apple ID?
If you use two different Apple IDs when you try to sync between your iPhone and iTunes, you're going to have a problem like this. Strange as it sounds, it does make sense. You buy tracks on iTunes PC/Mac using one Apple ID and then you try to sync them to your iPhone which is registered on another Apple ID, things aren't going to go as planned. It's strange why stuff like this happens (to good people!) but hey, make sure your ID is same just to see if things work fine!
4. Erase & Sync Again
For some users, this appears to work (especially when the files aren't corrupt or bad and they play just fine in other iDevices). You just remove all media content from your iPhone and then re-sync with iTunes (after you create a new library for all the music you want to sync).