Samsung Eternity SGH-A867

Hey so I got the Eternity June 2009 and have thoroughly enjoyed it...up to the point where about a month or two ago the music would no longer play. I tried to shock/restart it and everything, but nothing. Luckily it was/still is under the 1yr warranty, so I called customer service (AT&T) and they sent me a new phone. Worked great...until yesterday it decided to not play music anymore! The day before I was listening and playing music all day and nothing was wrong. I'm thinking about calling customer service again to get a new one but I want to see if there is something that I can do to fix it. So...any tips??