Hello shakedown_time , and welcome to the forums.
If all your music is on the computer, I would disable music syncing on the computer. Apply the change, sync, and Then re-eanble music syncing. this will delete all the music off the iPhone, and force itunes to re-loaded the music into the iPhone.
if that doesn't fix the issue I would restore.
http://support.apple.com/kb/HT1414
if your music is not in itunes, I would transfer your purchases to itunes.
http://support.apple.com/kb/HT1848
if you need help you can always call apple phone support 1-800-APL-CARE. but I don't think they're going to be open on xmas. You can also book an appointment for support a the apple store.
http://www.apple.com/retail/geniusbar/
If this resolve your issue please mark this thread as resolved. So people can focus on the un-resolved questions
good luck!
-S