Sorry to hear you are having difficulties but I am here to help. Keep in mind the answers I give depend entirely on the responses you give in return. So please be insightful and patient and maybe together we can solve your problem. Realizing the answers may not be pleasant for you to hear but you are requesting my expertise and I hope you will honor your good faith promise.
Do you ever get a picture? Could you provide the model number?
yes i get a picture and initially i have sound but after on about 15 mins the cracking popping sound starts like fire crackers and then sound goes out but picture stays on
The safest procedure from this moment on is not to watch this tv. If you are willing to take the wrapper of the back and operate it and defeat the door switch by putting the lamp door back on. From the rear operate the tv and try to analyze where this cracking is occurring. Observe closely the area that is called the ballast, you may find this by following the wires of the lamp socket into the ballast assembly. You will simply be visually observing DO NOT touch the devices when they are working exposure to shocking and high voltage exist. Perhaps you will be able to observe where the occurrence is and make corrective procedures. Thank you for allowing me to answer your question. Please click the ACCEPT button as this is how we are paid as experts our commission from your good faith deposit and consider leaving positive feedback. Do not hesitate to ask if you are in need of further assistance and please let me know if this resolves your problem.
What we need to know is exactly where this arcing noise is occurring. If you have taken the back wrapper off, as I suggested, and defeated the door switch by putting the door back on. As you request the set to come on in a low ambient noise area listen intently from the rear where the arcing is coming from. If this is a high voltage arc you may even see sparking at the ballast. If this is of audio frequency in nature then you will be able to isolate where it is coming from. You must be my ears and help isolate this symptom.