Buy another. if you don't want to wait, otherwise send it off unless you're happy to take it apart and do some serious component testing and then purchase a new component.
Ours broke a few months after we got it and the shop we bought it from replaced it,then the replacement one broke a couple of months ago and we sent it back to MS,they fixed it and had it back to us in just over a week along with a free month of XBOX live Gold.
You must stay away from the towel trick which apparently overheats your XBox causing the broken joins to re-solder themselves. If you do fix it yourself make sure you use a reputable guide to show you how. Take a look at this article.