I, also, am not receiving surround sound when viewing any program through the Xfinity box. When I review movies available through the Xfinity On Demand service I have noted note, in the associated notes, indicate the broadcast will include any of the surround sound technologies and when I watch any of those movies my A/V receiver does not receive a surround sound signal.
With respect to a previous reply -- it is not my HDMI or optical connections. When I watch movies provided by either Amazon Prime or Netflix my home theater system does receive and deliver surround sound. The difference is I watch Amazon Prime and Netflix through my smart TV with none of the Xfinity TV equipment being used.
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