jay spencer98,
Why not try hooking up your PS3 and cable box to your television, and then run the optical cable to your Onkyo? The surround sound (if you have it) will be supported by the optical out on the Samsung television (latest models, you didn't specify) and your picture will go directly to the television with the audio.
Keep me posted.
--HDTech
I have a new onkyo srt-606 receiver and a new samsung 58 inch plasma, and whenever i hook up an hdmi cable up to the receiver in from my playstation 3 or my cable box and out to my tv i get for lack of a better (not smart enough to call it anything else) term i get reverb help me please.

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