Unless the TV has some kind of specialized audio output jack, of which a headphone jack is not, it's a waste of time. There's really just no good way to route audio from a TV to a computer, period. The other way around is possible, though usually pointless.
The best option would be to find a surround receiver that work with whatever kind of TV setup you have. Then you can put speakers at various points in the room, and it won't need to be quite as loud.
I'm wanting to use my computer with speakers as a extension of my LCD {Vizio) TV. My room is large and to hear the TV while on computer, it has to be too loud for others in house. Is there anyway I can hard-wire (about 50' of wire) audio out of TV through headphone jack to computer audio input on Dell Desk top. I tried using the different ports on computer and the best I achieved was barely audible with a lot of background noise. I don't know if I need a booster are maybe a splitter at speaker connection???

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