iTunes won't sync my new music in my iPhone 5? Please help ASAP.

I was having the same issue and it was extremely frustrating for me. I tried everything short of restoring to an earlier backup, but what worked best for me was plugging in my phone and looking at summary>options> and clicking convert higher bit rate songs to 128 kbps. It worked for me, although I'll be the first to admit that I don't know why. I have about 2,900 songs in my library, so it did take an hour and a half for all of the songs to convert and then sync in their new forms, but I was so relieved to have the issue taken care of that I really didn't mind. I hope this helps, and good luck!!

Thank you so much for suggestion this! I tried many things and was also getting very frustrated. This worked for me, but I also am not sure why.

Thank you! I was having the same issue and stumbled across this and it worked!

I tried this but it still did not help! Any other ideas??😕