Tv making popping sound

IF IT WENT POP YOU PROBABLY LOST YOUR POWER SUPPLY. IF IT WENT POP YOU WILL NEED TO REPLACE SOME PARTS.

Sounds like the DLP lamp failed. You can decipher the Hitachi flashing red light. That should help to be sure.
The DLP lamp replacement is fairly straightforward and can be done with minimal tools

I have this same problem with my hitachi 55 inch ultravision luckily i have a warrenty still in effect so i called them and they said... Analog channels are not formatted for wide screen aspect (4, 6, and 10 ect.) this is a normal thing don't worry. It automatically returns to 4:3 because analog is full screen only, and it will return to 16:9 otherwise or whatever you have it set to. Nothing you can do but the good news is your TV isn't broken!

do you know the model?

Sounds like flyback shorting out and shutting down high voltage, causes TV to turn off for protection.

I would send in for repair cause this is big $$$ cost!

The loud "pop" sounds like high voltage arcing coming from one of the CRT's.....you may have to pull each CRT out and put silicon sealant on the anode connectors to prevent the arcing.(one of the CRT's may be arcing internally also and the only cure is to replace that CRT) If you let the arcing continue,it will short out the horizontal output transistor sooner or later.......

sounds like you need to do convergence.

He, he. Somebody activated the subtitle mode on the remote. Desactivate the CC mode on your menu and it'll go away or at least if you want CC put it in CC1 Text1

Check C702 near flyback xformer--if shorted, relace w/3KV cap.Example==102K/2KV replace with 102K/3KV SONY # 1-161-754-00.

It sounds like you have High Voltage arc, coming from back of set. Was there ever Horzontal lines in picture when this happen. Or did your picture ever get dark and miss some color? If any of this happen then it could be coming from High Voltage Transformer, and anodes leads coming from trans.I would say clean spark gap anode leads and make sure all are seated properly(tighten). It would help if you could have the back open and notice when the set does this to see if you see sparks and were from. Hope this helps. Remember be carefull around any Voltage.