Can't get 5.1 Dolby Digital Surround if I send audio to tv and then from tv to receiver?

I have a Comcast hdmi cable box. I hooked the box directly to the tv (Samsung) with a hdmi cable, and then hook the digital optical audio cable from tv to my Onkyo Surround receiver but couldn't get 5.1 Dolby Digital Surround. If I connect the audio from the cable box directly to the receiver via digital optical then I get 5.1 DDS. Anybody knows why? and is there a way to get 5.1 DDS using the first set up?

Can't get 5.1 Dolby Digital Surround if I send audio to tv and then from tv to receiver?
You gave the right amount of info to answer this question.





The Comcast Box is setup for Digital out.





Go into the menu, Then go to setup. Now to Audio





Here you'll find a setting for audio out.





You need to Highlight HDMI.





The audio will now follow the video down the HDMI cable.





This should fix your problem.
Reply:Some TVs need the optical output turned on, and set up to 5.1 surround sound. To be honest, it would be simpler just to use the later setup you mentioned.
Reply:make sure the comcast box is outputting the sound correctly.
Reply:You don't say how your TV to the receiver is hooked up and what connections you used, but that might be the source of your problem.


Besides the correct connection is to hook up your cable box to the receiver for sound and then to your TV.

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