Don't know the model or input/ouptut options on this set.
The audio system line input would be connected to the TV audio line outputs. There really isn't anything the installer could do to cause the failure of your TV by simply connecting equipment. In any case, if the audio was connected incorrectly it's unlikely to cause no picture. No sound maybe.
On TV's which "already has it's own integrated surround sound", I have on several occasions come across customers who have attemped to connect the TV's full loudspeaker output in parallel with a seperate hi-fi's loudspeakers. In that case there is usually a big bang, flash, smoke and probably no more TV or Hi-Fi. Also, on some TV's what appears to be RCA phono line level output socket, can be a full power output.
Far more likely, I'd suggest that there were some dry soldered joints in your TV just waiting to fail. The installer plugged into the TV sockets and the action was enough to disturb the circuit board and cause the joint to fail. In which case, it wouldn't be the installers fault that he was the unfortunate person to be last to touch your TV. It's called Murphys Law and all TV engineers and installers suffer it from time to time.
Cobweb
October 2005
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