Sounds like this might be blown or popped capacitors. There are a few guides on how to remove and replace them. It happened to an LCD 49" Samsung. I could hear a click/hiss and wouldn't turn on. After replacing the caps, TV was good as new again. Just make sure you get the same caps when replacing. They should be marked.
I too had a very similar problem with a 49" Samsung TV. After opening it, found there were 2 blown caps. Went to local electronic store, grabbed a soldering iron and replacement caps that matched, and after replacing them, TV was back up and running.