rubs chin...
i bought a couple 25foot, rca style cables and a couple female to female rca connectors. to run video and L plus Right from pc in basement to tv upstairs. i had slight quailty degradation in video. but audio was fine.
50foot pressed the limits of the cheapo rca cables. for video.
needless to say winter came. and being in a farm house. a mouse decided to come in and snake on cable

(have creavite audigy platium, that has the remote) just setup a standard remote extender and it worked for what was wanted.)
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find a cheap used / referbished computer. that has motherboard, cpu, some ram, sound card, network card and set it up as media server (old pc perhaps laying around?)
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get a tivo, and do a little hacking to turn them into home network media server.
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do a google search for "HTPC" aka "home theater pc" might bring up some results
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www.x10.com has extenders stero, video, camera etenders.
www.radioshack.com has some speaker extenders. that may work for need.
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