Loud cracking and zapping coming from tv,sounded like speakers,when it was first turned on.Was happening intermittently but now nothing.Checked power and fuse inside and nothing seems burnt or cracked

Either your main pcb has a defective auido circuit or speakers are bad. Doubt it is the speakers or it would do it all the time.

Sounds like defective capacitors on the power board

Check whether the power outlet has power. If it has, I suggest please do not attempt to switch on the TV, unless checked by a qualified service technician.

Toshiba model 57H93 worked perfectly last night. Turned off and went to bed. Turned on this morning, and nothing, it won't turn on. Checked all cords and cables, pushed reset button, and still won't turn on. What could cause this to happen?

if u are trying to connect the audio of ur tv as input to flow out from the home theater; this is a common thing; u need to replace the audio cable that connects the tv to 3565 with a good quality cable

Could it be vertical IC loose connection. It is sometimes connected with correct tuning. Check it for crack or wiggling connection best is to resolder.

I believe this is a dirt and contamination issue within the PS2. You need to open the case and thrououghly clean it out. This means thoroughly, Motherboard, and all. You will need a can of circuit board cleaner.

no doubt. replace LOT and horizontal output transformer with new one

Check u'r power socket.....
Power plug......
Or otherwise contact Retailer.

If you blew the fuse, the TV would do absolutely nothing - no lights, no sounds, nothing. It could be that the loud zapping noise you heard was the high voltage transformer arcing or shorting out. This could have caused the horizontal output transistor to short, and the set will not start as a result. You should have the set serviced by a qualified tech.