richlf,
It could be the abrupt shut off of the connected box. Does it happen if you turn off the television first?
--HDTech
Got my 52a750 Feb.09 Love this set but have noted a loud popping sound from the speakers when i shut it off at the same time as dirctv sat.box.Useing 1 remote to turn on and off the box and tv at the same time.Any one have this problem? Thanks to all.

Chowhound
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