This fix sounds bad but it's worth the trouble
Ok, so here’s a really annoying problem to have: you have a ton of music and you try to sync your entire music library to your iPhone, iPod Touch, or iPad and instead of getting all the music synced, you only get half or a quarter of the total songs! And on top of that, you have no idea why it won’t sync the rest of your songs.
I just updated my iPhone to iOS 5 and everything worked fine for more than a week. However, all of a sudden, music started to disappear from my phone! Every time I would sync the phone, fewer songs would be copied and I would get a message saying “X number of items could not be synced. Check iTunes”. Too bad iTunes didn’t give me any info either!
What I also noticed was that when I clicked on Music once I connected my iPhone (like below), a lot of the songs were greyed out!
So the above image shows how a normal collection should look when all your songs are syncing fine. Instead of the image above, a lot of the songs were greyed out and there were a strange sync icon to the left of the check marks. Not really sure what that meant, but I could not select any of the greyed out songs or do anything else with them.
I searched online and tried all kinds of crazy stuff like checking random boxes and changing settings, etc, but nothing worked. I figured it had to do with iCloud and iOS 5 since I didn’t have this partial song syncing problem before that.
Here’s what I tried and what worked for me:
Basically, you have to restore your phone. Sounds terrible and all, but it’s really not bad. Even if you just loaded up iOS 5 and performed a restore a week ago, just do it again. I promise it’s worth the trouble, otherwise you will have a flaky phone.
First thing to do is to backup the phone before you do this. You can do that by plugging in your phone and right-clicking on it and choosing Backup.
Once the backup has completed, you should disconnect your phone from the computer. Now you have to erase all content and reset your phone. Don’t worry, you’ll get all your music, messages, movies, songs, apps (with data) and everything else back if you did the backup.
On your iPhone or iPod Touch or iPad, go to Settings and then click on General. Scroll down to the bottom where it says Reset.
Then go ahead and click on the daunting Erase All Content and Settings. This will completely wipe out your phone and reset it to default.
Once your phone loads back up, you’ll be at the screen to setup iOS 5 again. When you get to the screen to setup as new iPhone or restore from iCloud or restore from iTunes, choose Restore from iTunes.
That’s it! Choose the most recent backup that you just made before deleting everything and you’ll have everything back to normal and all your songs will by synced instead of just half of them! If you are still having trouble syncing all your music to your device, post a comment here and I’ll try to help! Enjoy!