Made popping sound, no picture but, sound ok. makes noise when trying to change channels.

I keep seeing this kind of problems with lcd and other flat screen tv's

In order for a lcd, plasma, or dlp screen to power up, it requires a quick start system, and it uses capacitors to achieve this
Those capacitors are fragile, and all it takes is a quick on off on again, and ...pop!

The capacitors are more than likely blown. If your t.v. is under warranty, I would take it to the place you bought it for repairs, as this can be an expensive repair job.
Depending on how many of the capacitors failed, if could cost almost as much as the tv itself to fix it.