most TV will only do surround sound when the TV is using its built in tuner, any outside sources of sound will not pass or will only pass in stereo mode, not dolby digital.
TV companys are always looking for new ways to save on building cost, and this is just one of the ways to do that.
I'm looking to buy a 42 inch LCD, and recently when reading a review (http://alatest.com/apps/reviews/20984452/50512/TVs/JVC+LT-42P300/?ref=http%3A%2F%2Freviews.cnet.com%2Fflat-panel-tvs%2Fjvc-lt-42j300-42%2F4505-6482_7-33605899.html%3Ftag%3Dmncol%3Blst), it says that "The set's optical digital audio output is fed by its integrated broadcast tuner and provides no audio output from devices connected via HDMI." Is this the case for most lcd tv's? I was hoping to just input most of my devices into my tv, then run the digital out to my receiver for simplicity. Is there something that explicitly tells me if a tv's optical out will carry all of the television's sound?

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