If the source is HDMI, according to HDCP rules you should not get more than stereo to pass through. This is not a Samsung issue. I see this on all HDMI HDCP compliant gear.
It's interesting the cable box works but don't let that confuse you into thinking this should pass more than stereo. Rather than repeat all those prior discussions, why not call it in and hear it straight from the maker?
Bob
Hi, just got this model and had trouble with my Sony bluray player hdmi into a Sony STR-DA5400ES receiver, hdmi into the Samsung. It didn't recognize a 3d television so I hooked the BD directly to the Samsung, which fed digital optical audio to the receiver. The 3d disc played fine but the DTS didn't pass through. I ended up running optical out of the BD to the receiver and that did the trick. The Samsung sends DD to the receiver from my cable box fine. Any ideas? Thanks.

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